I need to differentiate this function:
secx^2-tanx^2+cosx. these are my steps:
f'(x)= secx^2*tanx^2-secx^2-sinx and do not know how to finish this but i know the first two terms are suppose to cancel. the answer is suppose to be -sin x.
And also, How does 2 sinx cosx translate to sin2x?
i don't think so. the question he asked was for a derivative, so i assume he wanted to know why someone would go between 2sin(x)cos(x) and sin(2x) to take a derivative (taking the derivative of the latter is much easier), so i didn't think a full proof was needed since it would just be an intermediate step for finding a derivative or something. besides, the wording he used kind of hinted he wasn't after a proof. he would more likely use the word "show" or "prove" or "proof" if he was after that