Skip to main content

Math Mathematical Methods in the Physical Sciences

Using polar coordinates (Problem 46), find out whether the following functions satisfy the Cauchy-Riemann equations. | z | 1 / 2 e i θ / 2

Using polar coordinates (Problem 46), find out whether the following functions satisfy the Cauchy-Riemann equations. | z | 1 / 2 e i θ / 2

Mathematical Methods in the Physical Sciences

Mathematical Methods in the Physical Sciences

3rd Edition

ISBN: 9780471198260

Author: Mary L. Boas

Publisher: Wiley, John & Sons, Incorporated

See similar textbooks

Videos

Textbook Question

Chapter 14.2, Problem 53P

Using polar coordinates (Problem 46), find out whether the following functions satisfy the Cauchy-Riemann equations.

| z | 1 / 2 e i θ / 2

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

Blurred answer

Chapter 14.2, Problem 52P

Chapter 14.2, Problem 54P

Students have asked these similar questions

Sketch the graph of f(x) = 3x^(3)+x^(2)-22x-24 First, fully factor f(x) and then analyze the graph . Use your information to sketch the graph. Check your results by graphing f(x) using a graphing program and checking the local maximum(s) and/or local minimum(s) for accuracy.

Answer in Matlab Script

Answwer in Matlab script

Chapter 14 Solutions

Mathematical Methods in the Physical Sciences

Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...

Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.1 - Find the real and imaginary parts u(x,y) and...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21 . Use the Cauchy-Riemann conditions to...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - 1 to 21. Use the Cauchy-Riemann conditions to find...Ch. 14.2 - Using the definition (2.1) of (d/dz)f(z), show...Ch. 14.2 - Using the definition (2.1) of (d/dz)f(z), show...Ch. 14.2 - Prob. 27P Ch. 14.2 - Using the definition (2.1) of (d/dz)f(z), show...Ch. 14.2 - Problem 28 is the chain rule for the derivative of...Ch. 14.2 - Problem 28 is the chain rule for the derivative of...Ch. 14.2 - Problem 28 is the chain rule for the derivative of...Ch. 14.2 - Using the definition of ez by its power series...Ch. 14.2 - Using the definitions of sin...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - Using series you know from Chapter 1, write the...Ch. 14.2 - In Chapter 12, equations (5.1) and (5.2), we...Ch. 14.2 - Prob. 44P Ch. 14.2 - Prob. 45P Ch. 14.2 - Prob. 46P Ch. 14.2 - Prob. 47P Ch. 14.2 - Using polar coordinates (Problem 46), find out...Ch. 14.2 - Prob. 49P Ch. 14.2 - Using polar coordinates (Problem 46), find out...Ch. 14.2 - Prob. 51P Ch. 14.2 - Prob. 52P Ch. 14.2 - Using polar coordinates (Problem 46), find out...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - Show that the following functions are harmonic,...Ch. 14.2 - It can be shown that, if u(x,y) is a harmonic...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate the following line integrals in the...Ch. 14.3 - Evaluate C(z3)dz where C is the indicated closed...Ch. 14.3 - 01+2iz2dz along the indicated paths:Ch. 14.3 - In Chapter 6, Section 11, we showed that a...Ch. 14.3 - In finding complex Fourier series in Chapter 7, we...Ch. 14.3 - If f(z) is analytic on and inside the circle z=1,...Ch. 14.3 - If f(z) is analytic in the disk z2, evaluate...Ch. 14.3 - Use Cauchys theorem or integral formula to...Ch. 14.3 - Use Cauchys theorem or integral formula to...Ch. 14.3 - Use Cauchys theorem or integral formula to...Ch. 14.3 - Use Cauchys theorem or integral formula to...Ch. 14.3 - Differentiate Cauchys formula (3.9) or (3.10) to...Ch. 14.3 - Use Problem 21 to evaluate the following...Ch. 14.3 - Use Problem 21 to evaluate the following...Ch. 14.3 - Use Problem 21 to evaluate the following...Ch. 14.4 - Show that the sum of a power series which...Ch. 14.4 - Show that equation ( 4.4 ) can be written as...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions find the first...Ch. 14.4 - For each of the following functions, say whether...Ch. 14.4 - For each of the following functions, say whether...Ch. 14.4 - For each of the following functions, say whether...Ch. 14.4 - For each of the following functions, say whether...Ch. 14.5 - If C is a circle of radius about z0, show that...Ch. 14.5 - Verify the formulas (4.3) for the coefficients in...Ch. 14.5 - Obtain Cauchys integral formula ( 3.9 ) from the...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Find the Laurent series for the following...Ch. 14.6 - Show that rule B is correct by applying it to...Ch. 14.6 - Derive (6.2) by using the limit definition of the...Ch. 14.6 - Prove rule C for finding the residue at a multiple...Ch. 14.6 - Prove rule C by using (3.9). Hints: If f(z) has a...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Prob. 33P Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - Find the residues of the following functions at...Ch. 14.6 - For complex z,Jp(z) can be defined by the series...Ch. 14.6 - The gamma function (z) is analytic except for...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - The values of the following integrals are known...Ch. 14.7 - In Example 4 we stated a rule for evaluating a...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - Using the rule of Example 4 (also see problem 21),...Ch. 14.7 - (a) By the method of Example 2 evaluate 0dx1+x4....Ch. 14.7 - Use the method of Problem 30(c) to evaluate...Ch. 14.7 - Use the method of Problem 30(c) and the contour...Ch. 14.7 - Evaluate the following integrals by the method of...Ch. 14.7 - Evaluate the following integrals by the method of...Ch. 14.7 - Evaluate the following integrals by the method of...Ch. 14.7 - Evaluate the following integrals by the method of...Ch. 14.7 - (a) Show that epx1+exdx=sinp for 0p1. Hint: Find...Ch. 14.7 - Using the same contour and method as in Problem...Ch. 14.7 - Evaluate e2x/3coshxdx. Hint: Use a rectangle as in...Ch. 14.7 - Evaluate 0xdxsinhx. Hint: First find the to ...Ch. 14.7 - The Fresnel integrals, 0usinu2du and 0ucosu2du,...Ch. 14.7 - If F(z)=f(z)/f(z) (a) show that the residue of...Ch. 14.7 - By using theorem (7.8), show that z3+z2+9=0 has...Ch. 14.7 - The fundamental theorem of algebra says that every...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - As in Problem 43 find out in which quadrants the...Ch. 14.7 - Use (7.8) to evaluate...Ch. 14.7 - Use (7.8) to evaluate z3dz1+2z4 around z=1.Ch. 14.7 - Use (7.8) to evaluate z3+4zz4+8z2+16dz around the...Ch. 14.7 - Use (7.8) to evaluate Csec2(z/4)dz1tan(z/4), where...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - Find the inverse Laplace transform of the...Ch. 14.7 - In equation (7.18), let u(x) be an even function...Ch. 14.8 - Let f(z) be expanded in the Laurent series that is...Ch. 14.8 - (a) Show that if f(z) tends to a finite limit as z...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Find out whether infinity is a regular point, an...Ch. 14.8 - Prob. 13P Ch. 14.8 - Evaluate the following integrals by computing...Ch. 14.8 - Evaluate the following integrals by computing...Ch. 14.8 - Observe that in Problems 14 and 15 the sum of the...Ch. 14.9 - In these problems you should be able to make rough...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - For each of the following functions w=f(z)=u+iv,...Ch. 14.9 - Describe the Riemann surface for w=z3 Ch. 14.9 - Describe the Riemann surface for w=z Ch. 14.9 - Describe the Riemann surface for w=lnz Ch. 14.9 - If w=f(z)=u(x,y)+iv(x,y),f(z) analytic, defines a...Ch. 14.9 - Verify the matrix equation dudv=Jdxdy, where J is...Ch. 14.9 - We have discussed the fact that a conformal...Ch. 14.9 - Compare the directional derivative...Ch. 14.10 - Prove the theorem stated just after (10.2) as...Ch. 14.10 - Assuming from electricity the equations...Ch. 14.10 - A fluid flow is called irrotational if V=0 where...Ch. 14.10 - Let a flat plate in the shape of a quarter-circle,...Ch. 14.10 - Consider a capacitor made of two very large...Ch. 14.10 - Prob. 6P Ch. 14.10 - Use the mapping function w=z2 to find the...Ch. 14.10 - Prob. 8P Ch. 14.10 - Find and sketch the streamlines for the flow of...Ch. 14.10 - Find and sketch the streamlines for the indicated...Ch. 14.10 - For w=ln[(z+1)/(z1)], show that the images of u=...Ch. 14.10 - Use the results of Problem 11 to solve the...Ch. 14.10 - Let the figure in Problem 12 represent (the cross...Ch. 14.10 - In the figure in Problem 12, let z=1 be a source...Ch. 14.10 - In Problem 14, the streamlines were the images of...Ch. 14.10 - Two long parallel cylinders form a capacitor. (Let...Ch. 14.11 - In Problems 1 and 2, verify that the given...Ch. 14.11 - In Problems 1 and 2, verify that the given...Ch. 14.11 - Liouvilles theorem: Suppose f(z) is analytic for...Ch. 14.11 - Use Liouvilles theorem (Problem 3 ) to prove the...Ch. 14.11 - In Problems 5 to 8, find the residues of the given...Ch. 14.11 - In Problems 5 to $8,$ find the residues of the...Ch. 14.11 - In Problems 5 to 8, find the residues of the given...Ch. 14.11 - In Problems 5 to $8,$ find the residues of the...Ch. 14.11 - In Problems 9 to 10, use Laurent series to find...Ch. 14.11 - In Problems 9 to $10,$ use Laurent series to find...Ch. 14.11 - Find the Laurent series of f(z)=ez/(1z) for z1 and...Ch. 14.11 - Let f(z) be the branch of z21 which is positive...Ch. 14.11 - In Problems 13 and $14,$ find the residues at the...Ch. 14.11 - In Problems 13 and 14, find the residues at the...Ch. 14.11 - In Problem 15 to 20, evaluate the integrals by...Ch. 14.11 - In Problem 15 to 20, evaluate the integrals by...Ch. 14.11 - In Problem 15 to 20, evaluate the integrals by...Ch. 14.11 - In Problem 15 to $20,$ evaluate the integrals by...Ch. 14.11 - In Problem 15 to 20, evaluate the integrals by...Ch. 14.11 - In Problem 15 to $20,$ evaluate the integrals by...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Verify the formulas in Problem 21 to 27 by contour...Ch. 14.11 - Evaluate 0xlnxdx(1+x)2 by using the contour of...Ch. 14.11 - Evaluate 0(lnx)21+x2dx by using the contour of...Ch. 14.11 - Show that PV0cos(lnx)x2+1dx=2cosh(/2) by...Ch. 14.11 - As in Section 7, find out how many roots the...Ch. 14.11 - As in Section 7, find out how many roots the...Ch. 14.11 - As in Section 7, find out how many roots the...Ch. 14.11 - As in Section 7, find out how many roots the...Ch. 14.11 - Show that the Cauchy-Riemann equations [see (2.2)...Ch. 14.11 - Show that a harmonic function u(x,y) is equal at...Ch. 14.11 - A (nonconstant) harmonic function takes its...Ch. 14.11 - Show that a Dirichlet problem (see Chapter 13,...Ch. 14.11 - Use the following sequence of mappings to find the...Ch. 14.11 - Use L13 of the Laplace transform table to find the...Ch. 14.11 - Evaluate by contour integration 0cos2(/2)122d....

Additional Math Textbook Solutions

Find more solutions based on key concepts

Fill in each blanks so that the resulting statement is true. Any set of ordered pairs is called a/an _______. T...

College Algebra (7th Edition)

Surface integrals of vector fields Find the flux of the following vector fields across the given surface with t...

Calculus: Early Transcendentals (2nd Edition)

Drug for Nausea Ondansetron (Zofran) is a drug used by some pregnant women for nausea. There was some concern t...

Introductory Statistics

Testing Hypotheses. In Exercises 13-24, assume that a simple random sample has been selected and test the given...

Elementary Statistics Using The Ti-83/84 Plus Calculator, Books A La Carte Edition (5th Edition)

Fifty-two percent of the students at a certain college are females. Five percent of the students in this colleg...

A First Course in Probability (10th Edition)

Solve the inequality 3x27 .

Precalculus

Knowledge Booster

Background pattern image

Math

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, subject and related others by exploring similar questions and additional content below.

Similar questions

SEE MORE QUESTIONS

Recommended textbooks for you

Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Trigonometry (MindTap Course List)
Trigonometry
ISBN:9781337278461
Author:Ron Larson
Publisher:Cengage Learning
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:9781305071742
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Trigonometry (MindTap Course List)
Trigonometry
ISBN:9781305652224
Author:Charles P. McKeague, Mark D. Turner
Publisher:Cengage Learning

Text book image

Algebra & Trigonometry with Analytic Geometry

Algebra

ISBN:9781133382119

Author:Swokowski

Publisher:Cengage

Text book image

Trigonometry (MindTap Course List)

Trigonometry

ISBN:9781337278461

Author:Ron Larson

Publisher:Cengage Learning

Text book image

Algebra and Trigonometry (MindTap Course List)

Algebra

ISBN:9781305071742

Author:James Stewart, Lothar Redlin, Saleem Watson

Publisher:Cengage Learning

Text book image

Trigonometry (MindTap Course List)

Trigonometry

ISBN:9781305652224

Author:Charles P. McKeague, Mark D. Turner

Publisher:Cengage Learning

SEE MORE TEXTBOOKS

Double and Half Angle Formulas | Analytic Trig | Pre-Calculus; Author: Brian McLogan;https://www.youtube.com/watch?v=eTdKgsyCmHs;License: Standard YouTube License, CC-BY