Hello, grooverandshaker!

You were off to a good start . . .

. .

The slope of a tangent to the curve is: .

When , the slope of the tangent is

. .

There is a stationary point at

That is, when , the derivative equals zero.

. . We have: .

The point is on the curve.

That is, when

. . We have: .

We have a system of equations: .

Subtract [1] - [2]: .

Substitute into [2]: .

Substitute into [3]: .

Therefore, the function is: .