$\frac{1-cos^2\left(y\right)}{cos^2\left(y\right)}$

$\left(\frac{3}{4}y+\frac{1}{6}\right)\left(\frac{3}{4}y-\frac{5}{8}\right)$

$\left(x^2-xy+y^2\right)dx-xydy$

$a2+2ax2+x^4$

$\left(-3\right)x\left(-2\right)x\left(+5\right)-\left(-8\right):\left(-2\right):\left(+4\right)+\left(-2\right)x\left(+5\right)x\left(-1\right)$

$y'-3x^2y=e^{\left(x^3+x\right)}$

$100x^4-60x^2b+9b^2$