SOLUTION: Here is a problem I can’t figure out. Radical sign with the radicand of x squared under it and the remainder is = x an identity (true for all values of x)?

Algebra ->  Radicals -> SOLUTION: Here is a problem I can’t figure out. Radical sign with the radicand of x squared under it and the remainder is = x an identity (true for all values of x)?       Log On


   

Question 83182: Here is a problem I can’t figure out.

Radical sign with the radicand of x squared under it and the remainder is = x an identity (true for all values of x)?


Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Are you asking if this is an identity?
sqrt%28x%5E2%29=x

Well lets try some values

Let x=2
sqrt%282%5E2%29=2 Plug in x=2

sqrt%284%29=2

2=2 works

Let x=3
sqrt%283%5E2%29=3 Plug in x=3

sqrt%289%29=3

3=3 works

Let x=4
sqrt%284%5E2%29=4 Plug in x=4

sqrt%2816%29=4

4=4 works

Now lets try some negative values

Let x=-2
sqrt%28%28-2%29%5E2%29=-2 Plug in x=-2

sqrt%284%29=-2

2=-2 doesn't work. Since this equation is not true sqrt%28x%5E2%29=x is not an identity