$3\sin^{2}x-8\sin x-3=0$

$8x^3-10x^2+2xy^2\:entre\:4x^2-3xy$

$\lim_{x\to1}\left(\frac{x^2-x-2}{x^2+2x-3}\right)$

$\lim_{x\to0}\left(\frac{x^{0.5}}{logx}\right)$

$\left|-20\right|\cdot\left|-2\right|\cdot\left|-5\right|$

$21xy^2+12x^2+3x^2-6xy^2-x^2$

$\left(\frac{7}{2}a^2b^3+\frac{1}{4}ab\right)\left(\frac{7}{2}a^2b^3-\frac{1}{4}ab\right)$