By using the factor theorem, show that $(x-3)$ is a factor of the polynomial $12 x^{3}-31 x^{2}-18 x+9$ and then factorise $12 x^{3}-31 x^{2}-18 x+9$
Evaluate the following products without multiplying directly
$78 \times 84$
If $x^{2}+k x+6=(x+2)(x+3)$ for all $x,$ then the value of $k$ is
The following expressions are polynomials? Justify your answer:
$\frac{1}{5 x^{-2}}+5 x+7$
Write the following cubes in expanded form
$(7 x-4 y)^{3}$