Solve-ax-3-bx-x-c-0-a-b-c-R-3-and-x-R-the-value-of-x-for-a-1-b-9-c-8-

Question Number 209986 by a.lgnaoui last updated on 28/Jul/24

Solve

{ax}^{3} - bx \sqrt{x} + c = 0

(a, b, c) \in R^{3} and x \in R

(t h e v a l u e o f x f o r a = 1, b = 9, c = 8)

Answered by mr W last updated on 28/Jul/24

l e t t = x \sqrt{x}

{a t}^{2} - b t + c = 0

\Rightarrow t = \frac{b \pm \sqrt{b^{2} - 4 a c}}{2 a}

\Rightarrow x = t^{\frac{2}{3}} = {(\frac{b \pm \sqrt{b^{2} - 4 a c}}{2 a})}^{\frac{2}{3}}

Commented by a.lgnaoui last updated on 28/Jul/24

thanks

thanks