Hmmmm. Wondering if you are taking calculus.
Calculus
y=sinxcosx
y'=0=cos^2x-sin^2x
cos^2x=sin^2x
tan^2 x=1
tanx= +-1
which occurs at increments of 45 degrees
x= +-PI/4, PI+-Pi/4
check that
find the values of x between 0 and 2 pi where the tangent line to the graph of y = sinxcosx is horizontal
1 answer