It is given that x and y are parametrically connected by the equations,
x=asecθ(1)
And,
y=btanθ(2)
Differentiate equation (2) with respect to θ.
dy dθ =b sec 2 θ
Differentiate equation (1) with respect to θ.
dx dθ =a( secθtanθ )
We know that,
dy dx = dy dθ dx dθ
Substitute the value of dy dθ and dx dθ .
dy dx = b sec 2 θ asecθtanθ dy dx = bsecθ atanθ dy dx =b× 1 cosθ × cosθ asinθ dy dx = b a cosecθ
Thus, the solution is dy dx = b a cosecθ.