Hello :D Here's a question that has been troubling me for awhile:
The equation of the curve is y = [2e^(-x/2)]cos x where 0 < x < pie, the curve has a stationary point of T.
[i] Find the x-coordinates of T.
[ii] Determine the nature of the stationary point at T.
---------------------------------------------------------------------
[i] For stationary point T, dy/dx = 0
By product rule, dy/dx = [d/dx (2e^-1/2x). cos x] + [d/dx cos x. 2e^(-1/2x)]
= [ -e^(-1/2x) . cos x ] + [ -sin x . 2e^(-1/2x) ]
EDIT: I can solve it already, thanks please help me close thread ^^