$\sec\left(a\right)\sec\left(a\right)\cot^2a$

$2x-9y-4x+6y$

$16ax-3by-10ax+4by$

$y=\frac{1}{2}\sen^{2}x$

$\int\left(x^6\left(\sqrt[4]{\left(x^7-9\right)}\right)\right)dx$

$\frac{sin\left(-\frac{5}{13}+\frac{\sqrt{15}}{4}\right)}{cos\left(-\frac{12}{13}+-\frac{1}{4}\right)}$

$2x-7;x=1$