$2\left(10\right)^4-\left(10\right)^2-1$

$\frac{\cos\left(u\right)}{\cos\left(u\right)-\sin\left(u\right)}=\frac{1}{1-\tan\left(u\right)}$

$3-5-8-11-4-13-9$

$4x^2-2x-8=0$

$2\left(a+6\right)-3\left(a-5\right)=18$

$\frac{dy}{dx}-y=\cos\left(e^{-x}\right)$

$125\cdot125$