Question

  giải giúp bài 5 câu b

Answer 1

Bài 5: 

b) Ta có: \(B=\dfrac{1+\sqrt{a}}{a\sqrt{a}+a+\sqrt{a}}:\dfrac{1}{a^2+\sqrt{a}}\)

\(=\dfrac{\sqrt{a}+1}{\sqrt{a}\left(a+\sqrt{a}+1\right)}\cdot\dfrac{\sqrt{a}\left(\sqrt{a}+1\right)\left(a-\sqrt{a}+1\right)}{1}\)

\(=\dfrac{\left(\sqrt{a}+1\right)^2\cdot\left(a-\sqrt{a}+1\right)}{a+\sqrt{a}+1}\)

Answer 2

\(B=\dfrac{1+\sqrt{a}}{a\sqrt{a}+a+\sqrt{a}}:\dfrac{1}{a^2+\sqrt{a}}=\dfrac{1+\sqrt{a}}{\sqrt{a}\left(a+\sqrt{a}+1\right)}.\left[\sqrt{a}\left(a\sqrt{a}+1\right)\right]=\dfrac{\left(1+\sqrt{a}\right)\sqrt{a}.\left(\sqrt{a}+1\right)\left(\sqrt{a}-a+1\right)}{\sqrt{a}\left(a+\sqrt{a}+1\right)}=\dfrac{\left(1+\sqrt{a}\right)^2.\left(\sqrt{a}-a+1\right)}{a+\sqrt{a}+1}\)

P/s: Ko biết có sai đâu ko mà kết quả ra dài thek nhở ??