Question

Решите неравенство 3х^2+2х-1 больше 0

Answer 1

$3x^2+2x-1 > 0 \\ D=4+12=16 \\ x_1=\frac{-2-4}{6}=-1 \\ x_2=\frac{-2+4}{6}=\frac{1}{3} \\ 3(x+1)(x-\frac{1}{3}) > 0$

---(+)--(○-1)--(-)----(○1/3)----(+)--->

$x \in (-\infty;-1)\cup (\frac{1}{3};+\infty)$