Value of x

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Value of x

by sydneyuni2014 » Fri Nov 25, 2016 3:02 am
I was able to solve the question but please help me with a small doubt

Is is true that any root of √1 and -√1 always equal 1 and -1 respectively?
Is is true that any root of √0 always equal to 1?

Thanks
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by flprg » Fri Nov 25, 2016 3:04 am
sydneyuni2014 wrote:I was able to solve the question but please help me with a small doubt

Is is true that any root of √1 and -√1 always equal 1 and -1 respectively?
Is is true that any root of √0 always equal to 1?

Thanks
1) Yes sqrt(1) = 1 and so -sqrt(1) = -1

2) No, sqrt(0) = 0. Because, 0 * 0 = 0
You might be confused with x^0 = 1 or 0^0 = 1

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by Matt@VeritasPrep » Fri Nov 25, 2016 2:39 pm
Conventionally speaking, √x only has one root, the positive one. (I'm assuming we're in friendly high school algebra, where x ≥ 0.)

For example, √4 ONLY has one root, 2, even though x² = 4 has TWO roots.

So √1 only has the root 1, and -√1 is just √1 * -1, so it only has one value as well.

√0 is similar, √0 = 0, it only has one root.