a) ĐKXĐ: x >= 1/2
Pt <=> 2x - 1 = 9
<=> x = 5 (thỏa ĐKXĐ)
b) ĐKXĐ: x>=4/3
Pt <=> 6x - 8 = 4
<=> 6x = 12 <=> x = 2 (thỏa ĐKXĐ)
c) ĐKXĐ: x >= 1
Pt <=> sqrt(x-1)=4
<=> x - 1 = 16 <=> x = 17 (thỏa ĐKXĐ)
d) ĐKXĐ: x >= -5
Pt <=> sqrt(x+5)=9
<=> x + 5 = 81
<=> x = 76 (thỏa ĐKXĐ)
e) ĐKXĐ: x >= 0
Pt <=> -2sqrt(x) = -6
<=> sqrt(x)=3
<=> x = 9 (thỏa ĐKXĐ)
f) ĐKXĐ: x >= 1
Pt <=> -sqrt(x-1)=-1
<=> sqrt(x-1)=1
<=> x - 1 = 1 <=> x = 2(thỏa ĐKXĐ)
a) \(đk:x\ge\dfrac{1}{2}\)
\(\Leftrightarrow2x-1=9\Leftrightarrow2x=10\Leftrightarrow x=5\left(tm\right)\)
b) \(đk:x\ge\dfrac{4}{3}\)
\(pt\Leftrightarrow6x-8=4\Leftrightarrow6x=12\Leftrightarrow x=2\left(tm\right)\)
c) \(đk:x\ge1\)
\(pt\Leftrightarrow\sqrt{x-1}=4\Leftrightarrow x-1=16\Leftrightarrow x=17\left(tm\right)\)
d) \(đk:x\ge-5\)
\(pt\Leftrightarrow\sqrt{x+5}=9\Leftrightarrow x+5=81\Leftrightarrow x=76\left(tm\right)\)
e) \(đk:x\ge0\)
\(pt\Leftrightarrow2\sqrt{x}=6\Leftrightarrow\sqrt{x}=3\Leftrightarrow x=9\left(tm\right)\)
f) \(đk:x\ge1\)
\(pt\Leftrightarrow\left(\sqrt{x-1}-1\right)^2=0\)
\(\Leftrightarrow\sqrt{x-1}-1=0\Leftrightarrow\sqrt{x-1}=1\)
\(\Leftrightarrow x-1=1\Leftrightarrow x=2\left(tm\right)\)
d) \(\sqrt{x+5}-2=7\)
\(\sqrt{x+5}=9\) Điều kiện: \(x>-5\)
\(\left(\sqrt{x+5}\right)^2=81\)
\(x+5=81\)
\(x=76\)
a: Ta có: \(\sqrt{2x-1}=3\)
\(\Leftrightarrow2x-1=9\)
hay x=5
b: ta có: \(\sqrt{6x-8}=2\)
\(\Leftrightarrow6x-8=4\)
hay x=2
