Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is a
transcluded archive page. While you can leave answers for any questions shown below, please ask new questions on one of the
current reference desk pages.
the contradictory part is that in the end, you get (√x-1/√x)^2 = 4, which will give you ±2; but √x which is √3+2√2 can be written as √(2-√1)^2 which is 2-√1 hence √x - 1/√x = -2
171.79.74.205 (
talk) 17:10, 6 May 2024 (UTC)reply
"... can be written ... ". No, it can't. Not sure if this is an honest question or just trolling. --
RDBury (
talk) 18:43, 6 May 2024 (UTC)reply
I'm not sure what they that is about but can I suggest that 1/(a+√b) = (a-√b)/{(a+√b)(a-√b)} might help?
NadVolum (
talk) 20:33, 6 May 2024 (UTC)reply
Clarify, please. Do you mean:
√x - (1/√x)
(√x - 1)/√x
√(x - 1)/√x
something else...?
I'd suggest using
LaTeX/
MathJax code within <math>...</math> tags to format the expressions like etc. Please see
WP:MATH for more info. --
CiaPan (
talk) 10:12, 7 May 2024 (UTC)reply
Sorry I misread the question and answered the wrong thing. But the square root of 3+2√2 is plus or minus 1+√2 and the original answer of ±2 is correct.
NadVolum (
talk) 11:07, 7 May 2024 (UTC)reply
√x is usually taken to mean the positive square root when x is positive. At least that's the notation used in
Square root. That would make the answer 2. --
RDBury (
talk) 16:58, 7 May 2024 (UTC)reply
Only if you say the square root, and nobody has said that. It also doesn't matter whether the original √2 is positive or negative.
NadVolum (
talk) 17:07, 7 May 2024 (UTC)reply
The issue here is not a lack of the definite article, but the meaning of the symbol Conventionally, when is a real number, denotes the same as so is definitely positive. --
Lambiam 18:15, 7 May 2024 (UTC)reply
The answer is 2 if the meaning of "√x−1/√x" is (√x) − (1/√x). But note that the question uses "√3+2√2" with the meaning √3 + 2√2. --
Lambiam 18:25, 7 May 2024 (UTC)reply