$25a^2+70ab+49b^2$

$64x^2-40xy+16y^2$

$\lim_{x\to0}\left(\left(\frac{1}{x}\right)^{\tan\left(x\right)}\right)$

$\frac{9}{4}\left(\frac{10}{3}x-4\right)-\frac{1}{4}\left(2x-8\right)$

$3-4\cdot\left(2-3\right)\cdot2+\left(4+3+2\right)\cdot\left(-1\right)\cdot2$

$\frac{\left(sin\left(a+b\right)\right)}{cos\:\left(a-b\right)}+1$

$3=x^2$