document.write( "Question 293344: how would you solve this proof?
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Algebra.Com's Answer #211778 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"+%28sqrt%286%29-sqrt%282%29%29%2F4+=++sqrt%282-sqrt%283%29%29%2F2+\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"+sqrt%286%29-sqrt%282%29+=++2%2Asqrt%282-sqrt%283%29%29+\" Multiply both sides by the LCD 4 to clear out the fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"+sqrt%286%29-sqrt%282%29+=++sqrt%284%29%2Asqrt%282-sqrt%283%29%29+\" Rewrite \"2\" as \"sqrt%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+sqrt%286%29-sqrt%282%29+=++sqrt%284%282-sqrt%283%29%29%29+\" Combine the roots on the right side using the identity \"sqrt%28x%29%2Asqrt%28y%29=sqrt%28x%2Ay%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"+sqrt%286%29-sqrt%282%29+=++sqrt%288-4%2Asqrt%283%29%29+\" Distribute and multiply\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%288-4%2Asqrt%283%29%29+=+sqrt%286%29-sqrt%282%29+\" Rearrange the equation.\r
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\n" ); document.write( "\n" ); document.write( "We essentially have a nested radical on the left side. In general, we have an equation in the form \"sqrt%28a%2Bb%2Asqrt%28c%29%29=sqrt%28d%29%2Bsqrt%28e%29\". The goal from here is to square both sides, gather like terms, and equate rational and irrational parts. So let's do these next tasks. \r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%288-4%2Asqrt%283%29%29+=+sqrt%286%29-sqrt%282%29+\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+%28sqrt%286%29-sqrt%282%29%29%5E2+\" Square both sides.\r
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\n" ); document.write( "\n" ); document.write( " FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+6-2%2Asqrt%286%29%2Asqrt%282%29%2B%28sqrt%282%29%29%5E2+\" Square \"sqrt%286%29\" to get 6.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+6-2%2Asqrt%286%29%2Asqrt%282%29%2B2+\" Square \"sqrt%282%29\" to get 2.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2Asqrt%286%29%2Asqrt%282%29+\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2Asqrt%286%2A2%29+\" Combine the roots on the right side using the identity \"sqrt%28x%29%2Asqrt%28y%29=sqrt%28x%2Ay%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2Asqrt%2812%29+\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2Asqrt%284%2A3%29+\" Factor 12 into 4*3 (take note that 4 is a perfect square)\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2Asqrt%284%29%2Asqrt%283%29+\" Break up the root using the identity given above.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-2%2A2%2Asqrt%283%29+\" Take the square root of 4 to get 2.\r
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\n" ); document.write( "\n" ); document.write( "\"8-4%2Asqrt%283%29+=+8-4%2Asqrt%283%29+\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "From here, we can see that the two numbers are equal since the rational parts are equal and the irrational parts are equal. So this confirms that \"+%28sqrt%286%29-sqrt%282%29%29%2F4+=++sqrt%282-sqrt%283%29%29%2F2+\"\r
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\n" ); document.write( "\n" ); document.write( "Note: Ideally, you'll only manipulate one side to transform it into the other. However, this is much more difficult to do with nested radicals. I find that algebraic manipulations suffice in this case. As a final check, you can use a calculator to find that both sides approximate to the value 0.258819045 (which helps verify the answer).
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