Find `dy/dx` at `t = pi/4`, when x = 2 cos t - cos 2 t and y = 2 sin t - sin 2 t.

Find dy/dx at t = pi/4 , when x = 2 cos 2t and y = 2 sin t - sin 2t

Find dy/dx at t = pi/4 when x e^(-t) (sin t + cos t ) and y = e^-t (sin t - cost)

Find dy/dx , when x = a(cos t + log |tan t/2|) andy = a sin t, 0 < t < pi/2

Find dy/dx when x = e^t (sin t + cos t), y = e^t (sin t - cos t)

Show that the equation of normal at any point 't' on the curve: x = 3 cos t - cos^3 t and y = 3 sint - sin^3 t is: 4(ycos^3t - x sin^3t)=3 sin 4t .

Find (dy)/(dx) if x = sin t and y = cos 2t .

Find dy/dx when x = a sin^2 t, y = b cos^2 t

Find dy/dx when x= a cos^3 t , y = b sin^3 t

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