$\left(-5\right)-\left(-4\right)+2$

$5a\:+\:7a\:$

$\left(c+10\right)^5$

$sinx-sin3x$

$\lim_{x\to2}\left(\frac{1}{\left(6x-12\right)}\right)$

$f\left(x\right)=x^3-x^2\sin\left(x\right)$

$\frac{1+\frac{1}{\cos\:\left(y\right)}}{\frac{\sin\:\left(y\right)}{\cos\:\left(y\right)}+\sin\:\left(y\right)}=\frac{1}{\sin\left(y\right)}$