Question
Asked Oct 25, 2019

Find the exact values of x and y of the following: 

-400 degrees 

-150 degrees 

250 degrees  

do not enter cos or sin, use exact values

check_circleExpert Solution
Step 1

The period of a function is defined as the interval where the function repeats itself.

f(x+T) f(x), where T is period
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f(x+T) f(x), where T is period

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Step 2

The period of sin and cos is 360°.

So get the values of sin (-400°) and cos (-400°).

cos(-400)cos(-360° -40
cos(-40
cos(40°)
0.766
sin(-400esin(-360° -40
=sin(-40
=-sin(40°
=-0.6427
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cos(-400)cos(-360° -40 cos(-40 cos(40°) 0.766 sin(-400esin(-360° -40 =sin(-40 =-sin(40° =-0.6427

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Step 3

The expansion formula is to b...

sin (x+y)sin xcos y + cos xsin y
cos (x+y)cos xcos y-sin xsin y
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sin (x+y)sin xcos y + cos xsin y cos (x+y)cos xcos y-sin xsin y

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