Question

4x³+18x²+27x+13,5 = 0

Answer 1

$4x^3+18x^2+27x+13,5 =0$
$40x^3+180x^2+270x+135 =0$
разделим на (2x+3)
$frac{40x^3+180x^2+270x+135}{2x+3} = left(2x+3right) left(20x^2+60x+45right) =0$
Тогда можно записать
$(2x+3) =0$
$x_1 = -1,5$
и
$20x^2+60x+45 =0$
$x_{2,3}= frac{-bpmsqrt{D}}{2a} = frac{-60pmsqrt{0}}{40} =-1frac{1}{2}$
$x_{2,3} = -1frac{1}{2}$

Ответе: $x_1 = -1,5$