$-1\left(3-4\right)-1^2$

$\left(5x^4+\frac{1}{2}x^3-1x^2-3x-4\right).2x^3+6x^2-1x$

$f\left(x\right)=\left(5x+1\right)^2x.x^4$

$\frac{x}{5a^4b^{4\:}}^5+c=\frac{x}{5ab}^5+c$

$\left(\frac{1}{3}y-\frac{1}{2}\right)^2$

$\frac{1}{1+sinx}-\frac{sin\left(-x\right)}{cos^2x}=sec^2x$

$y^2+4y-21$