$4r^2-12r+9$

$\frac{\frac{\cos\left(90+a\right)}{\sin\left(90+a\right)}}{-2\sin\left(a\right)^2}=\csc\left(2a\right)$

$\sqrt{\frac{9}{2}y+\frac{15}{2}-\frac{15}{2}}\ln\sqrt{2y^2}+5+c$

$x^2+2x-35\ge0$

$12\left(3x\:+\:2\right)^2\:+\:17\left(3x\:+\:2\right)\:-\:5$

$\frac{x-3}{x^2-9}=\frac{x+6}{x+3}$

$2\left(9y+\frac{1}{2}\right)$