Banerjee,
Thank you for your response.For folks who are interested in why we assume positive root for radical sign i.e. square root sign,please refer to the following link:
https://www.jamesbrennan.org/algebra/rad ... _roots.htm
++++
Quote:
To avoid confusion between the two we define the symbol (this symbol is called a radical) to mean the principal or positive square root.
The convention is:
For any positive number x,
(x)^1/2 is the positive root, and
-(x)^1/2 is the negative root.
+++
Rgds,
Anna
banerjeea_98 wrote:
MA, I disagree when u say square root of 4 is only +2. Every positive number has two square roots, one positive and one negative. Both 2 and
-2 are square roots of 4.
This can be a typical DS question: x is an integer, is x = 3 ?
1) x^2 = 9 .....Here we get 2 values +3 and -3 thus insufficient.
However, understanding Anna ques now, it is true that when we use a radical sign i.e. square root sign, by definition, it means the principal or positive sqaure root only, thus as Anna said:
(X^2)^1/2 = |X| for all real numbers X