All square roots are either positive or negative

In the problem which I attempted today

√(x+1)-√(x-1) = √(4x-1)

the solution is 5/4

It is NOT insolvable, as given in the answer, because when put in as a check the result is

√(5/4+1)-√(5/4-1) = √(4*5/4-1) √(9/4) -√(1/4) = √(5-1) 3/2 +or- 1/2 = 2 Hence either 3/2 + 1/2 = 2 YES 3/2 - 1/2 = 2 NO Therefore the answer given is incorrect BECAUSE ALL SQUARE ROOTS ARE EITHER POSITIVE OR NEGATIVE

regards JR123

Easy Math Editor

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`2^{34}`	$2^{34}$
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Comments

I believe you are referring to this problem.

The solution is not $\frac{5}{4}$ .

The correct answer, as you pointed out, is "No solution".

In future, if you have any issues with a problem, you can report it directly by selecting "Report problem" from the menu. This will allow the problem creator to respond to you directly.

Calvin Lin Staff - 4 years, 4 months ago

In solving Maths problems it is often necessary to discard a negative result and accept the positive one when two possibilities are found. I suggest you look at my analysis again.

John Rimmer - 4 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$