The square root of x is a number that, when squared, gives x. So, the square root of 9 is +3 or -3.
I believe what is typically called the "square root sign" is actually the principal square root sign.
But in most mathematics educations the negative root is not dealt with until much later. But once you learn about it, it tends to stick!
It's not so much us not dealing with something more complex than it is us wanting everything to be a function.
]]>I believe that the use of the radical sign √ refers only to the positive root, so you could say:
√9=+3 and -√9=-3
But in most mathematics educations the negative root is not dealt with until much later. But once you learn about it, it tends to stick!
]]>I guess it depends on what level is being taught. When students are first taught "square root" thay are only taught the positive root, so we should really have a function "psqrt" or something that doesn't suffer from the two-result problem.
So if it is only the positive root then x≥-6 is right, otherwise only -6 is valid.
]]>since f(x) = sqrt(x+ 6), you are right in that x + 6 >= 0
so you have that x >= -6. (not <)
and that is youre domain, x >= -6.
]]>x + 6 > 0
-
subtract 6 both sides
x < -6
-
(-00,-6) < is the domain of F
?
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