It is given that x and y are parametrically connected by the equations,
x=sint(1)
And,
y=cos2t(2)
Differentiate equation (2) with respect to t.
dy dt = d( cos2t ) dt dy dt =−2sin2t
Differentiate equation (1) with respect to t.
dx dt = d( sint ) dt dx dt =cost
We know that,
dy dx = dy dt dx dt
Substitute the value of dy dt and dx dt .
dy dx = −2sin2t cost dy dx = −2( 2sintcost ) cost dy dx =−4sint
Thus, the solution is dy dx =−4sint.