Need clarification on squareroots

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Need clarification on squareroots

by iikarthik » Sun Jan 11, 2009 11:38 am
hi,

Is X^2=36 and x= sqrt(36) same?


My understanding: X^2 = 36 means x=+6 or X=-6

But i read somewhere that x= sqrt(36)=6 i.e the solution would always be a positive value.so need clarification on this
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by cramya » Sun Jan 11, 2009 12:43 pm
.

Case 1:

When a square root symbol is involved we only consider the prinicipal square(non negative real square root) root of the number. x is just +6 when x = sqrt(36)


Case 2:

x^2 = 36



x^2 = (6) ^2
x^2 = (-6) ^ 2

As u can notice nowhere are we involving the square root symbol here.

Regards,
CR

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by arzanr » Sun Jan 11, 2009 1:01 pm
Would it be correct to say that in the case of x = sqrt (36), unless it is specifically mentioned that x is a positive integer, it is possible that x could be -6.

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by cramya » Sun Jan 11, 2009 1:04 pm
Would it be correct to say that in the case of x = sqrt (36), unless it is specifically mentioned that x is a positive integer, it is possible that x could be -6
IMO It would always be a +6 when u see a square root symbol.