$4\left(1+a\right)^2-4\left(1+a\right)\left(b-1\right)-\left(b-1\right)^2$

$x\left(1+y^2\right)^{\frac{1}{2}}dx=y\left(1+y^2\right)^{\frac{1}{2}}dy$

$3-2\cdot3-2-1\cdot2$

$\frac{\frac{\left(y^2\right)}{x\left(x+y\right)}}{2x}$

$3x\:\left(4+y\right)$

$5n^2+17n+6$

$x-\frac{x}{2}$