Find `(dy)/(dx)` , when `x=a t^2` and `y=2\ a t`

Find (dy)/(dx) , when x=a\ cos^3t and y=at .

Find (dy)/(dx), when x=(3a t)/(1+t^2)" and "y =(3a t^2)/(1+t^2)

Find (dy)/(dx) , when x=(1-t^2)/(1+t^2) and y=(2t)/(1+t^2)

Find (dy)/(dx) , when x=(2t)/(1+t^2) and y=(1-t^2)/(1+t^2)

Find (dy)/(dx) , if x=a t^2, y=2a t .

Find (dy)/(dx), when x=(e^t+e^(-t))/2 \ a n d \ y=(e^t-e^(-t))/2

Find (d^2y)/(dx^2) , if x=a t^2,\ \ y=2a t .

Find (dy)/(dx) , when y=e^xlog(1+x^2)

If x and y are connected parametrically by the equations given, without eliminating the parameter, Find (dy)/(dx) . x=2a t^2, y=a t^4

find (dy)/(dx) , when y = sin u ,, u = e^(sqrt t) and t = log x