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3(x)^1/2 = (x)^1/2 help

  • Thread starter frozen7
  • Start date
164
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3(x)^1/2 = (x)^1/2

How come there are two answers for this equation?? 0 and 1/3
 

siddharth

Homework Helper
Gold Member
1,110
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Your equation is
[tex] 3 \sqrt{x} = \sqrt {x} [/tex]

How is 1/3 a solution?
On substituting 1/3 in the Left Hand side you get [tex]\sqrt 3 [/tex]

On substituting 1/3 in the Right Hand side you get [tex] \frac {1}{\sqrt 3} [/tex]

So LHS is not equal to RHS.
This means that 1/3 is not a solution
 
16
0
You should first square each side to get rid of the square root, giving you:

9x = x

And x = 0 should be your only answer
 

Zurtex

Science Advisor
Homework Helper
1,120
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frozen7 said:
3(x)^1/2 = (x)^1/2

How come there are two answers for this equation?? 0 and 1/3
Erm:

[tex]3 \sqrt{x} = \sqrt{x}[/tex]

[tex]3 \sqrt{x} - \sqrt{x} = 0[/tex]

[tex]2 \sqrt{x} = 0[/tex]

[tex]\sqrt{x} = 0[/tex]

I think there is only one solution to that.
 
551
1
Phoenix314 said:
You should first square each side to get rid of the square root, giving you:

9x = x

And x = 0 should be your only answer
You don't need to. It should be clear that x = 0, otherwise you'd have 3 = 1.
 

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