Question

решить неравенство 4x +7<=2/x

Answer 1

4х+7≤ $frac{2}{x}$
4х²+7х≤2
4х²+7х-2≤0
D=7²-4*4*(-2)=49+32=81
$x_{1} = frac{-7+9}{2*4} = frac{2}{8} = frac{1}{4}$
$x_{2} = frac{-7-9}{8} = frac{-16}{8} = -2$