[Stupid Question] Square root of one?

Question

√y^2=√1
Do i write down both 1 and -1?
The topic is Systems of Non-Linear Equations

Answer 1

Are you asking:

specifically for √1 which is defined to be the positive square root, so takes just one value, which is 1,

or are you solving y^2 = 1, in which case y could be either of the square roots of 1, which are +/-√1, ie y could be 1 or -1

?

Answer 2

sqrt(1) is defined as 1.

Answer 3

1. Sqrt(1) refers to the unique non-negative number that squares to give 1. This is 1.
2. There are two solutions to the equation you give though, which are -1 and 1.