$\log_{30}\left(c-1\right)+\log_{30}\left(c-8\right)=1$

$2\:cos^2\:x\:-\:cos^4\:x\:+\:\left(1-\:cos^2\:x\right)^2$

$\int2x^3cos\:\left(x^2\right)dx$

$\log4\:\left(5x-1\right)=3$

$\lim_{x\to1}\left(\frac{\left(x^2+4x-5\right)}{\ln\:\left(x\right)}\right)$

$15\left(\cos^2\left(x\right)\right)+16\left(\sin^2\left(x\right)\right)=15+\sin^2\left(x\right)$

$\left(x+2\right)^2<-x$