Rút gọn P=[1/cănx−1−1/cănx]:[cănx+1/cănx−2 −cănx+2/cănx−1]
cho P= \(\left[{}\begin{matrix}1\\\sqrt{X}-1\end{matrix}\right.-\dfrac{1}{\sqrt{X}}]:\left[{}\begin{matrix}\sqrt{X}+1\\\sqrt{X}-2\end{matrix}\right.-\dfrac{\sqrt{X}+2}{\sqrt{X}-1}]\)
a) tim DKXD
b.rút gọn P
c.tìm x để P=\(\dfrac{1}{4}\)