Question

rút gọn biểu thức

\(\dfrac{a-b}{\sqrt{a}-\sqrt{b}}-\dfrac{\sqrt{a}^3-\sqrt{b}^3}{a-b}\)

Answer 1

=\(\dfrac{\left(a-b\right)\left(\sqrt{a}-\sqrt{b}\right)}{\left(\sqrt{a}-\sqrt{b}\right)\left(\sqrt{a}-\sqrt{b}\right)}-\dfrac{\sqrt{a^3}-\sqrt{b^3}}{a-b}\)

=\(\dfrac{\sqrt{a^3}-\sqrt{b^3}}{a-b}-\dfrac{\sqrt{a^3}-\sqrt{b^3}}{a-b}\)

=\(0\)