Y' = 5(-sin(x)sin(x)+cos(x)cos(x)) - 2/5(cos(x)(-sin(x)))Y' = 5(cos(2x)) - 2/5(-sin(2x))Y' = 5cos(2x) + 2sin(2x)
Y' = 5(-sin(x)sin(x)+cos(x)cos(x)) - 2/5(cos(x)(-sin(x)))
Y' = 5(cos(2x)) - 2/5(-sin(2x))
Y' = 5cos(2x) + 2sin(2x)