$-8.2+y=-52.1$

$\lim_{x\to\infty}\left(\sqrt{x^2+8x}-x\right)$

$\left(a^3b^4\right)^{-2}$

$\int_0^{\frac{\pi}{4}}\left(\sec^2t\sqrt{\tan t}\right)dt$

$12\pi^3-15\pi^2+30\pi$

$\int\frac{6x-1}{\left(x-4\right)\left(x+3\right)}dx$

$\int\cos\left(a\right)-\cos\left(2x\right)dx$