Find the value of at if and

y and x are given in terms of θ hence we have to first find and

and then divide both to get

Let us first find

y = ae^θ(sinθ + cosθ)

Differentiating with respect to θ using uv rule which says that if u and v are some functions then (uv)’ = u’v + uv’

Now let us find

x = ae^θ(sinθ – cosθ)

Differentiating with respect to θ using uv rule

Substituting (a) and (b) in (i)

We have to find at hence put in