The polynomial $p(x)=x^{4}-2 x^{3}+3 x^{2}-a x+3 a-7$ when divided by $x+1$ leaves the remainder $19 .$ Find the values of $a .$ Also find the remainder when $p(x)$ is divided by $x+2.$
Factorise the following:
$16 x^{2}+4 y^{2}+9 z^{2}-16 x y-12 y z+24 x z$
Write the degree of the following polynomials
$5$
Evaluate the following products without multiplying directly
$84 \times 79$
If both $x-2$ and $x-\frac{1}{2}$ are factors of $p x^{2}+5 x+r,$ show that $p=r$