Question

respondam. ....................

Answer 1

$\int\limit \frac{-10x^2}{x^2+1} \, dx = -10\int\limit \frac{x^2}{x^2+1} \, dx \\ = -10\cdot(x-arc\;tx\;(x)+c)\\ = -10x+10\cdot\;arc\;tx\;(x)-10c\\ = -10x+10\cdot\;arc\;tx\;(x)-c$