Question

Answer 1

a: \(\Leftrightarrow\sqrt{x-1}+2\sqrt{x-1}-5\sqrt{x-1}=-2\)

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

=>căn x-1=1

=>x-1=1

=>x=2

b: \(\Leftrightarrow\sqrt{x-1}\cdot\dfrac{1}{2}-\dfrac{9}{2}\sqrt{x-1}+3\sqrt{x-1}=-17\)

=>-1/2*căn x-1=-17

=>căn x-1=34

=>x-1=1156

=>x=1157

c: \(\Leftrightarrow8\sqrt{x+1}-5\sqrt{x+1}+2\sqrt{x+1}=20\)

=>5*căn x+1=20

=>căn x+1=4

=>x+1=16

=>x=15

d: \(\Leftrightarrow\sqrt{3x}+15\sqrt{3x}-12\sqrt{3x}=16\)

=>4*căn 3x=16

=>căn 3x=4

=>3x=16

=>x=16/3

e: \(\Leftrightarrow2\sqrt{x-1}-2\sqrt{x-1}-3\sqrt{x-1}=20\)

=>-3*căn x-1=20(vô lý)

f: =>\(\dfrac{2}{3}\sqrt{15x}-\dfrac{1}{3}\sqrt{15x}=11\)

=>căn 15x=33

=>15x=1089

=>x=72,6