Mathematics 9709 · AS & A Level · Algebra

Algebra — practice question

The polynomial $p(x)$ is given by $p(x)=ax^3+bx^2-17x-a$, where $a$ and $b$ are constants. It is also known that $(x+2)$ is a factor of $p(x)$, and that the remainder on dividing $p(x)$ by $(x-2)$ is $28$.
(i)[5]

Determine the values of $a$ and $b$.

(ii)[3]

Hence, factorise $p(x)$ fully.

(iii)[2]

State how many roots the equation $p(2^y)=0$ has, with justification.

Worked solution & mark scheme

This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: Put $x=-2$ into the expression and set it equal to zero

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI