A tangent line is a straight line, so is of the form

where m is the gradient and c is the y-intercept.

To find the gradient of this tangent, we need to differentiate the function and evaluate it at that point.

so .

At the point , .

So the gradient of the tangent at is 1.

We know that when , so the y-intercept is 1.

Thus the equation of the tangent is