Evaluate the following products without multiplying directly
$88 \times 86$
$4 x^{2}+11 x-3$ is a $\ldots \ldots . .$ polynomial.
Find the quotient and the remainder when $2 x^{2}-7 x-15$ is divided by
$2 x+1$
If $(x-1)$ is a factor of $x^{3}+7 x^{2}+a x-3,$ then find the value of $a$.
If $x+1$ is a factor of the polynomial $2 x^{2}+k x,$ then the value of $k$ is