Factorise
$8 x^{3}+125 y^{3}+343-210 x y$
Find $p(1), p(2)$ and $p(4)$ for each of the following polynomials
$p(x)=x^{3}+9 x^{2}+23 x+15$
Find the value of $m$ so that $2 x-1$ be a factor of $8 x^{4}+4 x^{3}-16 x^{2}+10 x+m.$
If $p(x)=x^{2}-4 x+3,$ evaluate $: p(2)-p(-1)+p\left(\frac{1}{2}\right)$
If $x+1$ is a factor of $a x^{3}+x^{2}-2 x+4 a-9,$ find the value of $a$.