sqrt(16) - how many answers?
By Murray Bourne, 21 Sep 2005
I had a heated debate with some colleagues yesterday when I claimed that √16 = 4. They were strongly advocating that there are 2 answers, ±4.
I pointed out that there is a difference between this question:
Solve for x: x2 = 16
and this question:
Evaluate x: x = √16.
The first has 2 solutions, the second has one answer.
See the 38 Comments below.