We have given two parametric equation:

Let us Assume t= tan θ

So,

Therefore,

sin x=sin 2θ

x=2θ ---(i)

Also,

Tan y=tan 2θ

y=2θ ---(ii)

from equation (i) and (ii)

y=x

now, differentiate w.r.t x

Hence, dy/dx=1