Question
Asked Oct 31, 2019
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Evaluate the integral
x cos(3x) dx
Note: Use an upper-case "C" for the constant of integration
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Evaluate the integral x cos(3x) dx Note: Use an upper-case "C" for the constant of integration

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Expert Answer

Step 1

Given:

Sxcos (3x)dx
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Sxcos (3x)dx

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Step 2

Integration by parts:

(x) d | dx
dx
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(x) d | dx dx

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Step 3

Taking x as first function and cos(3x) as second function and I...

d
Jxcos (3x) dr= xfcos(3x) d
cos(3x) d dx+C
x
sin (3x
xcos (3x) dr= x
sin (3x
dx C
xsin (3x)
Jxcos (3x) dx=
sin(3x) dx+ C
x sin (3x)
(-cos 3x)
+C
1
Jxcos (3x) dr=
3
x sin (3x)
cos ( 3.x)
+C
9
Jxcos (3x) dr=
3
Jxcos (3x) dt
3x sin(3x)+cos (3x)+C
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d Jxcos (3x) dr= xfcos(3x) d cos(3x) d dx+C x sin (3x xcos (3x) dr= x sin (3x dx C xsin (3x) Jxcos (3x) dx= sin(3x) dx+ C x sin (3x) (-cos 3x) +C 1 Jxcos (3x) dr= 3 x sin (3x) cos ( 3.x) +C 9 Jxcos (3x) dr= 3 Jxcos (3x) dt 3x sin(3x)+cos (3x)+C

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Math

Calculus