Evaluate the following products without multiplying directly

$84 \times 79$

Expand the following:

$(4 a-b+2 c)^{2}$

Which of the following expressions are polynomials in one variable and which are not $?$ State reason for your answer. If the given expression is a polynomial, state whether it is a polynomial in one variable or not

$x^{2}+x-3+\frac{4}{x}$

Check whether $p(x)$ is a multiple of $g(x)$ or not :

$p(x)=x^{3}-5 x^{2}+4 x-3, \quad g(x)=x-2$

Factorise the following quadratic polynomials by splitting the middle term

$x^{2}+14 x+33$

Find the quotient and the remainder when $x^{3}+x^{2}-10 x+8$ is divided by

$x+3$