$\csc\left(x\right)=3,1$

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

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

$\lim_{x\to0}\left(2x^2+1\right)^x$

$h^2m^4-m^2$

$\left(-35\right)-9\cdot2$

$8cos2x$