A curve has the parametric equations
x=tan2t,y=cost,0<t<π2 x = \tan^2 t, \quad y = \cos t, \quad 0 < t < \frac{\pi}{2} x=tan2t,y=cost,0<t<2πFind an expression for dydx\displaystyle \frac{dy}{dx}dxdy in terms of ttt.
Find an equation of the tangent to the curve when t=π4\displaystyle t = \frac{\pi}{4}t=4π
Find a cartesian equation for the curve.