$9m^2-25n^2$

$\left(1+x^2\right)\left(x^6-12x^4+60x^2\right)$

$\int_3^7\left(\sqrt{1+\left(2y\right)^2}\right)dx$

$5\log_x\left(y\right)+3\log_x\left(y\right)-\left(\log_x\left(2a\right)-\log_x\left(b\right)\right)$

$25x^4+1-1$

$e^{\left(x+y\right)}\cdot y'=2\cdot x$

$x^2-12x-13=0$