Question

giải các phương trình sau 

Answer 1

b: ĐKXĐ: x>=1

\(PT\Leftrightarrow5\sqrt{x-1}-\dfrac{15}{2}\cdot\dfrac{\sqrt{x-1}}{3}=6+\sqrt{x-1}\)

=>\(\sqrt{x-1}\cdot\left(5-\dfrac{15}{2\cdot3}\right)-\sqrt{x-1}=6\)

=>\(\sqrt{x-1}\left(5-\dfrac{5}{2}-1\right)=6\)

=>\(\sqrt{x-1}\cdot\dfrac{3}{2}=6\)

=>\(\sqrt{x-1}=4\)

=>x-1=16

=>x=17(nhận)

c: ĐKXĐ: x>=5

\(PT\Leftrightarrow2\sqrt{x-5}-\dfrac{1}{3}\cdot3\sqrt{x-5}+\sqrt{x-5}=4\)

=>\(2\sqrt{x-5}=4\)

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

=>x-5=4

=>x=9(nhận)

d: ĐKXĐ: x>=-1

\(PT\Leftrightarrow4\sqrt{x+1}-3\sqrt{x+1}+2\sqrt{x+1}=16-\sqrt{x+1}\)
=>\(3\sqrt{x+1}+\sqrt{x+1}=16\)

=>\(\sqrt{x+1}=4\)

=>x+1=16

=>x=15(nhận)