$\left(-x^2+8x-12\right)\left(-x^2+8x-12\right)$

$\frac{4^4.27^2.8^3.81^2}{16^2.27^5.4^6.9^1}$

$1x^2+3x-1$

$4\:-\:\left(1\:-\:8\right)$

$5\tan\left(x\right)+\frac{1}{3}\sec\left(x\right)$

$5\sin\left(x\right)=2+\frac{4}{\csc\left(x\right)}$

$b^2+\left(\frac{1}{a}+\frac{1}{b}\right)\left(\frac{1}{b}+\frac{1}{c}\right)+\left(\frac{1}{n}+\frac{1}{m}\right)^2;\:m=6;\:n=\frac{1}{4};\:b=4;\:a=3$