If $x+y=12$ and $x y=27,$ find the value of $x^{3}+y^{3}$
Multiply $x^{2}+4 y^{2}+z^{2}+2 x y+x z-2 y z$ by $(-z+x-2 y)$
Give an example of a polynomial, which is:
$(i)$ monomial of degree $1$
$(ii)$ binomial of degree $20$
$(iii)$ trinomial of degree $2$
Evaluate
$(98)^{2}$
Expand the following:
$(3 a-5 b-c)^{2}$