$1\cdot2<6$

$12.\:\left(-9\right)\:.\:\left(-12\right)$

$\int_{14.018\cdot10^{-3}}^{15\cdot10^{-3}}\left(21\sin\left(\frac{2\pi x}{0.015}\right)+6\right)\left(\cos\left(\frac{2\pi x}{0.015}\right)\right)dx$

$3b+3b+2c^2+2c^2+c^2$

$\frac{x^2+3x-10}{x+1}$

$63+63+63+63$

$\int\frac{1}{\left(4+x\right)^{\frac{3}{2}}}dx$