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[ringwers]

I have my final exam tomorrow...help!! How do I find the increasing intervals of f(x)=sinxcosx once I've gotten to f'(x)=cos(2x)?? Thanks!

 

[skeeter]

set cos(2x) = 0 to determine critical values of x in your given domain, then determine those intervals where f'(x) > 0 (f is increasing) and where f'(x) < 0 (f is decreasing).