The function is  and point .

Slope of the tangent line is the derivative of the function at .

Consider .

Apply derivative on each side with respect to .

.

Power rule of derivatives : .

Constant rule of derivatives :. 

.

Substitute  in .

Slope of the tangent line is .

Find the tangent line equation.

Point slope form of line equation : .

Substitute  and  in the point-slope form.

The tangent line equation is .

Graph:

Graph the function  and tangent line .

The differential equation is .

The tangent line equation is .