$23x\cdot3x$

$\left(5-2p\right)\left(5+2p\right)$

$x^4-100x^3+x^5-100x^2$

$\frac{1}{2}\cdot7\left(15+5\right)$

$\int_0^{1-x}\left(x^3y\right)dy$

$2x^2-3x^2-11x^2+8x^2$

$2\left(a+b\right)^2\:-\:\frac{1}{2}\:\left(c\:+\:n\right)\:cuando\:a\:=\:3,\:b\:=\:4,\:c\:=\:\frac{1}{3},\:n\:=\:\frac{1}{4}$