$598-31$

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

$\left(x+3\right)^2-8x-9=0$

$x^3-2x^2+6+x^2-7x+4+x^3-4x+5$

$f\left(x\right)=\frac{x^2-1}{\left(x+1^2\right)^2}$

$12.01\:-\:4.897$

$16x^4-12x^2+4x$