$\left|5\:\right|-7$

$\left(\frac{3}{7}a-9b\right)\left(\frac{7}{2}a+6b\right)$

$2cos^2x+4=5-cosx$

$\frac{\sec\left(x\right)^6+\csc\left(x\right)^6}{\sec\left(x\right)^6.\csc\left(x\right)^6}$

$x^2>16$

$\frac{cos^2xtan^2\left(-x\right)-1}{cos^2x}$

$\frac{\left(2x^3-3x^2+5-7\right)}{\left(x-2\right)}$