$\frac{d^4}{dx^4}\left(y=-5x^5+\frac{x^4}{2}-6x^3+2x^2-3x\right)$

$\frac{1}{4}a-\frac{1}{3}b+4\frac{1}{2}b-\frac{5}{6}c+3\frac{2}{3}a+1\frac{2}{3}c-1\frac{1}{2}a+\frac{1}{6}b+9\frac{1}{2}c$

$3.01+5$

$\frac{d}{dx}\frac{3x-7}{x+2}$

$\left(y+x^2\right)dx=xdy$

$\frac{1-\sin^2\left(a\right)}{\cos\left(a\right)}=\sin\cdot\cos^2\left(a\right)$

$-12a;\:a=-3$