solve-x-x-2-4-x-2-6-

Question Number 172007 by Mikenice last updated on 23/Jun/22

s o l v e :

x \sqrt{x^{2} + 4} - x^{2} = - 6

Answered by puissant last updated on 23/Jun/22

x \sqrt{x^{2} + 4} = x^{2} - 6

\Rightarrow x^{2} (x^{2} + 4) = x^{4} - 12 x^{2} + 36

\Rightarrow x^{4} + 4 x^{2} = x^{4} - 12 x^{2} + 36

\Rightarrow 16 x^{2} - 36 = 0

\Rightarrow {(4 x)}^{2} - 6^{2} = 0

\Rightarrow 4 x = 6 o r 4 x = - 6

\Rightarrow x = \frac{3}{2} o r x = - \frac{2}{3}

S = {- \frac{2}{3}; \frac{2}{3}}

Commented by Mikenice last updated on 23/Jun/22

p l e a s e s i r r e c h e c k y o u r s o l u t i o n