$16\:-\:4\:x^2$

$\lim_{x\to0}\left(\frac{log\left(x^2+\sqrt{2}x+1\right)-\frac{x^2}{2}-\sqrt{2}x}{x^2}\right)$

$\left(5+6b\right)^2\left(25+60b+36b^2\right)^3$

$-6m-24$

$\left(\frac{1}{2}x^{2}+2y\right)\cdot\left(\frac{1}{2}x^{2}-2y\right)=\frac{1}{4}x^{4}-4y^{2}$

$9x^2-36x$

$-7x-3y+3z=12$