$x^2+6x-72$

$\int\ln\left(\frac{1}{3}x\right)dx$

$^{\left(1+x\right)}^2$

$2\left(13x+12x^{2}\right)+9x^{3}+1$

$\lim_{x\to0}\frac{\left(x-4\right)^2-16}{x}$

$\sin\left(x+1\right)=0$

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