$5\left(3+4n\right)$

$\int-5x\cdot\sin\left(x\right)dx$

$-\left(\frac{2}{3}y^2\right)^3$

$\int\frac{3x-1}{\left(x+2\right)\left(x-4\right)}dx$

$\cos\left(x-\frac{\pi}{6}\right)-\cos\left(x+\frac{\pi}{6}\right)=\sin\:x$

$\lim_{x\to0}\sqrt{\frac{4\cos x}{\sin x+\cos x}}$

$\frac{-25a^{12}b^{9}}{-5a^{6}b^{3}}$