$\int\cos\left(x\right)\tan\left(x\right)dx$

$2sen\left(2x\right)sen\left(x\right)=-2cos\left(3x\right)sen\left(x\right)$

$2a^5b^4c-3a^4b^3c^2+\frac{1}{3}a^3b^2c^3$

$\frac{d}{dx}x+12$

$\left(x-1\right)ln\left(2x+1\right),\:a=1$

$\int e^{\frac{x^4}{4}}x^3dx$

$3+\tan^2\left(x\right)-\frac{2}{\tan^2\left(x\right)}$