Question 1
Find the slope of the curve y = cos

at the point where x =

.
◦ -

◦ -

◦ -

◦ -

◦ The slope is not defined at x =

.
Question 2
Find all points in the interval [0, π] where the curve y = 2 sin
2 x - sin(2x) has a horizontal tangent line.
◦

and

◦

and

◦

and

◦

and

◦ The tangent line is never horizontal.