$\frac{sin^4\left(y\right)-\cos^4\left(y\right)}{\sin\left(y\right)-\cos\left(y\right)}=\sin\left(y\right)+\cos\left(y\right)$

$3.5\cdot10^6$

$\cos^2\left(x\right)+\tan^2\left(x\right)+\sin^2\left(x\right)-\sec^2\left(x\right)$

$\int5\sqrt{5x+1}dx$

$5a^2-3a-14$

$.\:\left(4x\:-\:2y\right)^2$

$\int x\sin\left(\frac{1}{7}\right)\left(x\right)dx$