Chapter 8 - Section 8.4 - Equations Quadratic in Form - Exercise Set - Page 635: 7

{$1$}

Since, $u^2+u-2=0$ Factorize the expression as follows: $(u+2)(u-1)=0$ or, $u=${$-2,1$} Replace $u$ with $\sqrt x$, we have $\sqrt x=-2$ which has no solution. or, $\sqrt x=1$ and $x=1$ Hence, our solution set is $x=${$1$}