The tangent to the curve
at the point
Given that
has -coordinate show that has -coordinate and find the coordinate of Prove that the tangent does not intersect the curve for a third time.
Find the equation of the tangent at the point
You will need to expand the cubic in order to differentiate it.
In the end, you should find yourself solving the equation
It is possible to guess the solutions to this equation.
For part (b), you know that
Use long division to factorise this cubic and hence prove that the only two solutions represent the