Definite Integral of a Power Function

$\frac{1}{2}*(\sqrt{4}-\sqrt{1})=0.5*(2-1)=0.5$

$\sqrt{4+1}-\sqrt{1+1}=\sqrt{5}-\sqrt{2}$

$2*(\sqrt{4}-\sqrt{1})=2*(2-1)=2$

$\sqrt{4}-\sqrt{1}=2-1=1$