Question

Answer 1

giải giúp em bài 15

 

Answer 2

15:

a: DKXĐ: x>=0; x<>4

\(PT\Leftrightarrow\sqrt{x}-1=3\left(\sqrt{x}-2\right)=3\sqrt{x}-6\)

=>\(-2\sqrt{x}=-5\)

=>căn x=5/2

=>x=25/4

b: ĐKXĐ: x>=0; x<>1

\(PT\Leftrightarrow2\left(\sqrt{x}+1\right)=\sqrt{x}-1\)

=>\(2\sqrt{x}+2-\sqrt{x}+1=0\)

=>\(\sqrt{x}+3=0\)(vô lý)

c: ĐKXĐ: x>=0; x<>4

\(PT\Leftrightarrow\sqrt{x}+10=-2\left(\sqrt{x}-2\right)=-2\sqrt{x}+4\)
=>\(\sqrt{x}+2\sqrt{x}=4-6=-6\)

=>3*căn x=-6(vô lý)

d: ĐKXĐ: x>=0

\(PT\Leftrightarrow3x+\sqrt{x}=3\sqrt{x}+5\)

=>\(3x-2\sqrt{x}-5=0\)

=>\(\left(3\sqrt{x}-5\right)\left(\sqrt{x}+1\right)=0\)

=>3*căn x-5=0

=>x=25/9