Answer
${2x}{tan(x^{2})}-\frac{tan\sqrt x}{2\sqrt x}$
Work Step by Step
$G(x)$ = $\int_{\sqrt x}^{x^{2}}tan(t)dt$ = $\int_{0}^{x^{2}}tan(t)dt$ - $\int_{0}^{\sqrt x}tan(t)dt$
apply chain rule with FTC we get
$G'(x)$ = $tan(x^{2})(2x)-tan(\sqrt x)(\frac{1}{2}x^{-\frac{1}{2}})$ = ${2x}{tan(x^{2})}-\frac{tan\sqrt x}{2\sqrt x}$