$\frac{1}{sin^4\:x\:-cos^4\:x}=-sec2x$

$\left(3y^1\cdot4y^3\right)^3$

$\int_0^{\frac{\pi}{2}}\left(\frac{1}{1-\sin\left(x\right)}\right)dx$

$-6+9+3-6+4-1+5-3+6$

$15d^2c^4-10d^3c^6f$

$\int_0^8ln\left(x^2+x+2\right)dx$

$\lim_{x\to0}\left(\frac{\sin\left(x^4\right)}{x}\right)$