$35\:x\frac{2}{7}$

$\lim_{x\to\infty}\cos\left(2\tan^{-1}x\right)$

$\cos^4b-\sin^4b=\cos2b$

$\frac{7x^3-2x+4x-5x^5+3x^3-2}{x-3}$

$\frac{x^2+x-2}{x^2+5x+6}\left(15m-2\right)+\left(\frac{3}{2}\right)$

$4\sqrt{5}3\sqrt{5}$

$7sec^2\left(x\right)-2tan^2\left(x\right)=2+5sec^2\left(x\right)$