Toán Lớp 9: Rút gọn biểu thức:
$M$ = ($\frac{1}{\sqrt{a}-1}$ – $\frac{1}{\sqrt{a}}$) :$(\frac{\sqrt{a}+1}{\sqrt{a}-2}$ -$\frac{\sqrt{a}+2}{\sqrt{a}-1})$
Leave a reply
Register Now
Login
Lost Password
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Toán Lớp 9: Rút gọn biểu thức:
$M$ = ($\frac{1}{\sqrt{a}-1}$ – $\frac{1}{\sqrt{a}}$) :$(\frac{\sqrt{a}+1}{\sqrt{a}-2}$ -$\frac{\sqrt{a}+2}{\sqrt{a}-1})$
Comments ( 1 )
$M=\left(\dfrac{1}{\sqrt{a}-1}-\dfrac{1}{\sqrt{a}}\right):\left(\dfrac{\sqrt{a}+1}{\sqrt{a}-2}-\dfrac{\sqrt{a}+2}{\sqrt{a}-1}\right)$
$=\dfrac{1}{a-\sqrt{a}}:\dfrac{3}{a-3\sqrt{a}+2}$
$=\dfrac{1\cdot \left(a-3\sqrt{a}+2\right)}{\left(a-\sqrt{a}\right)\cdot \:3}$
$=\dfrac{a-3\sqrt{a}+2}{\left(a-\sqrt{a}\right)\cdot \:3}$
$=\dfrac{a-3\sqrt{a}+2}{3\left(a-\sqrt{a}\right)}$