$-\left(2a+3b-4\right)+\left(a-2b+5\right)-\left(4a-7b-6\right)$

$\cot\frac{x}{2}=1$

$\frac{\cos\left(v\right)}{1+sin\left(v\right)}+\frac{1+sin\left(v\right)}{cos\left(v\right)}=2sec\left(v\right)$

$\frac{1+3.5^2}{\sqrt{\frac{11}{2}-\frac{1}{2}}}$

$\sqrt{3x}+3\sqrt{48x}+8\sqrt{27x}$

$\left(-7\right)\cdot\left(-7\right)\cdot\left(-7\right)\cdot x\cdot x\cdot x\cdot y$

$\int\left(3x\left(9-x^{-9}\right)\right)dx$