Question

For `f(x)=1/cosx` what is the equation of the tangent line at `x=(3pi)/2`?

Answer 1

There is no tangent line at `x=(3pi)/2`.

Explanation:

`cos((3pi)/2) = 0`, so

`f((3pi)/2)` does not exists,

so there is no point on the graph of `f` that has `x=(3pi)/2`.

Therefore, there can be no tangent line at `x=(3pi)/2`.