$\left(2x^2+1\right)\left(4x^2-2x+1\right)=8x^4+1$

$\left(4x+2y+5\right)^2$

$-11\:x\:8$

$cos^4\left(x\right)-sen^4\left(x\right)=0$

$xtangxdx-ycosxdy=0$

$\left(2-\sqrt{2}\right)x^2+\left(4-5\sqrt{2}\right)x+2\le0$

$\cot\left(x\right)^2-\cos\left(x\right)^4\csc\left(x\right)^2=\cos\left(x\right)^2$