How to solve for x ?

• February 19th 2006, 01:42 AM
totalnewbie
How to solve for x ?
• February 19th 2006, 02:25 AM
CaptainBlack
Quote:

Originally Posted by totalnewbie

$
x^{1/2}+x-2=0
$

Substitute $y=\sqrt{x}$, then the equation becomes:

$
y^2+y-2=0
$

then solve for $y$, and examine all the possible solution to
determine which are sensible.

Note: As $y^2+y-2$ factorises to $(y-1)(y+2)$
so does $x^{1/2}+x-2$ to $(x^{1/2}-1)(x^{1/2}+2)$.

RonL