Question

Help meeeee

Answer 1

1:

a: ĐKXĐ: x>=0 và x<>1

\(P=\dfrac{x-\sqrt{x}-x-\sqrt{x}}{x-1}\cdot\dfrac{\sqrt{x}+1}{2}\)

\(=-\dfrac{2\sqrt{x}}{x-1}\cdot\dfrac{\sqrt{x}+1}{2}=-\dfrac{\sqrt{x}}{\sqrt{x}-1}\)

b:Khi x=căn 4+2căn 3 thì

\(P=\dfrac{-\sqrt{3}-1}{\sqrt{3}+1-1}=\dfrac{-\sqrt{3}-1}{\sqrt{3}}=\dfrac{-3-\sqrt{3}}{3}\)

c: P=-2

=>căn x/căn x-1=2

=>2*căn x-2=căn x

=>căn x=2

=>x=4