DKXD a>0
ở tử có chứa mẫu
\(a^2+\sqrt{a}=\sqrt{a}.\left(\sqrt{a^3}+1\right)=\sqrt{a}.\left(\sqrt{a}+1\right)\left(a-\sqrt{a}11\right)\)
cái kia cũng thế
\(A=\frac{a^2+\sqrt{a}}{a-\sqrt{a}+1}-\frac{2a+\sqrt{a}}{\sqrt{a}}+1\left(ĐK:x>0\right)\)
\(=\frac{a^2+\sqrt{a}}{\left(a-\sqrt{a}+1\right)}-2\sqrt{a}-1+1\)
\(=\frac{a^2+\sqrt{a}-2a\sqrt{a}+2a-2\sqrt{a}}{a-\sqrt{a}+1}\)
\(=\frac{a^2-2a\sqrt{a}+2a-\sqrt{a}}{a-\sqrt{a}+1}=\frac{\sqrt{a}.\left(\sqrt{a}-1\right)\left(a-\sqrt{a}+1\right)}{a-\sqrt{a}+1}=\sqrt{a}\left(\sqrt{a}-1\right)\)