$f+f$

$35-6x=8x^2$

$\left(\frac{2}{4}x^3\right)\left(\frac{1}{6}x\right)$

$\frac{\sin\left(x\right)}{\cos\left(x\right)}\left(\frac{1}{\sin\left(x\right)}+\frac{\cos\left(x\right)}{\sin\left(x\right)}\right)$

$\frac{d}{dx}\ln\sqrt{1-x^2}$

$20+5xy+4y^2+10+y^2$

$-5-\:-1\left(-10\right)$