$sen4x.csc\left(x+30^{\circ}\right)=1\:\cdot$

$\lim_{k\to\infty}\left(\frac{\left(k+1\right)x}{3\left(k-1\right)}\right)$

$- 4 x ^ { 2 } + 10 x + 24 = 0$

$2-2\cdot10+8$

$\left[6\left(x-1\right)-8x\right]$

$\left(x^{a-1}-3x^{a-2}\right)^2$

$\log\left(800x+600\right)-\log x=3$