document.write( "Question 1202968: Evaluate the three radicals. Though they look similar, each one is different.
\n" ); document.write( " \"sqrt%2816%2F49%29\"
\n" ); document.write( "- \"sqrt%2816%2F49%29\"
\n" ); document.write( "\"sqrt%28-16%2F49%29\"
\n" ); document.write( "-\"sqrt%28-16%2F49%29\"\r
\n" ); document.write( "\n" ); document.write( "Which of the above square roots can be simplified with a real number answer and what is the simplified value?\r
\n" ); document.write( "\n" ); document.write( "Which of the above square roots cannot be simplified and why can they not be simplified?
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Algebra.Com's Answer #838185 by math_tutor2020(3816)\"\" \"About 
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\n" ); document.write( "\"sqrt%2816%2F49%29+=+sqrt%28%284%5E2%29%2F%287%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2816%2F49%29+=+%28sqrt%284%5E2%29%29%2F%28sqrt%287%5E2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%2816%2F49%29+=+4%2F7\" The square root and squaring exponents cancel out\r
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\n" ); document.write( "\n" ); document.write( "Through similar steps,
\n" ); document.write( "\"-sqrt%2816%2F49%29+=+-4%2F7\"\r
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\n" ); document.write( "\n" ); document.write( "Therefore, the first two items can be simplified to a real number result.\r
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\n" ); document.write( "\n" ); document.write( "----------------------------\r
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\n" ); document.write( "\n" ); document.write( "The last two items cannot be simplified to a real number result because of the negative under the square root.\r
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\n" ); document.write( "\n" ); document.write( "But if we involve the imaginary number \"i+=+sqrt%28-1%29\", then we can say
\n" ); document.write( "\"sqrt%28-16%2F49%29+=+%284%2F7%29i\"
\n" ); document.write( "and
\n" ); document.write( "\"-sqrt%28-16%2F49%29+=+-%284%2F7%29i\"
\n" ); document.write( "Both of these results are complex numbers of the form a+bi\r
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\n" ); document.write( "\n" ); document.write( "----------------------------\r
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\n" ); document.write( "\n" ); document.write( "The reason a negative number is not allowed under the square root is to note how \"x%5E2\" produces nonnegative values when x is a real number.\r
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\n" ); document.write( "\n" ); document.write( "Examples:
\n" ); document.write( "\"x+=+3\" leads to \"x%5E2+=+3%5E2+=+3%2A3+=+9\" which is nonnegative
\n" ); document.write( "\"x+=+0\" leads to \"x%5E2+=+0%5E2+=+0%2A0+=+0\" which is nonnegative
\n" ); document.write( "\"x+=+-5\" leads to \"x%5E2+=+%28-5%29%5E2+=+%28-5%29%2A%28-5%29+=+25\" which is nonnegative
\n" ); document.write( "There is no way to have \"x%5E2\" be negative when x is real.\r
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\n" ); document.write( "\n" ); document.write( "So if \"x%5E2+=+y\" then \"x+=+sqrt%28y%29\" shows that we can only plug in nonnegative values for y.
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