$\frac{d}{dx}3\cos x+2\sin2y=1$

$\frac{d}{dx}\left(\left(5x-2\right)^2\cdot\left(8x^2+2\right)^3\right)$

$\lim_{x\to\infty}\left(\frac{\left(2^x+3^x\right)}{\pi^x}\right)$

$\lim_{x\to0}\left(\frac{1-\ln\left(b\right)}{1+\ln\left(b\right)}\right)^x$

$x^2-6x-40=0$

$1-2\sin\:^2\left(x\right)=\frac{1-tan^2x}{1+tan^2x}$

$tan\left(-x\right)sin\left(-x\right)$