SOLUTION: Rewrite cos(x-7pi/4) in terms of sin(x) and cos(x)

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Question 1203100: Rewrite cos(x-7pi/4) in terms of sin(x) and cos(x)
Answer by ikleyn(52803) About Me  (Show Source):
You can put this solution on YOUR website!
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Rewrite cos(x-7pi/4) in terms of sin(x) and cos(x)
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Use the formula of difference of arguments for the cosine function
in combination with table values of sine and cosine functions


    cos%28x-7pi%2F4%29 = cos%28x%29%2Acos%287pi%2F4%29 + sin%28x%29%2Asin%287pi%2F4%29 = 

                 = %28sqrt%282%29%2F2%29%2Acos%28x%29 - %28sqrt%282%29%2F2%29%2Asin%28x%29.    ANSWER

Solved.