document.write( "Question 36954: Need help understand these.\r
\n" ); document.write( "\n" ); document.write( "2) Is ( square root of x)^2=x an identity (true for all nonnegative values of x)?
\n" ); document.write( "Answer:
\n" ); document.write( "Explain your answer in this space.
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Algebra.Com's Answer #27136 by psbhowmick(878)\"\" \"About 
You can put this solution on YOUR website!
\"%28sqrt%28x%29%29%5E2=x\" is an identity.\r
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\n" ); document.write( "\n" ); document.write( "ILLUSTRATION:
\n" ); document.write( "Suppose x = 8, then \"sqrt%28x%29\" = \"sqrt%288%29\" = either \"2sqrt%282%29\" or \"-2sqrt%282%29\".
\n" ); document.write( "Now, as both \"%282sqrt%282%29%29%5E2\" and \"%28-2sqrt%282%29%29%5E2\" are equal to 8 (= x) hence the truth of the statement made above can easily be verified.\r
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\n" ); document.write( "\n" ); document.write( "However, if x be a negative number, say, x = -4.
\n" ); document.write( "Then \"sqrt%28-4%29\" is imaginery and equals \"2i\" [where i = \"sqrt%28-1%29\"]. So \"%28sqrt%28x%29%29%5E2\" = \"%282i%29%5E2\" = \"4i%5E2\" = -4 = x.
\n" ); document.write( "Thus, the proposition is also valid for negative real values of 'x'.
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