document.write( "Question 1087364: if a^2 + 1 = a find the value of a^3.
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Algebra.Com's Answer #701628 by jim_thompson5910(35256)\"\" \"About 
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\"a%5E2+%2B+1+=+a\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+1-1+=+a-1\" Subtract 1 from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+=+a-1\" Simplify. Call this equation (1)\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2+%2B+1+=+a\" Go back to the original equation\r
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\n" ); document.write( "\n" ); document.write( "\"a%2A%28a%5E2+%2B+1%29+=+a%2Aa\" Multiply both sides by 'a'\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E3+%2B+a+=+a%5E2\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E3+%2B+a-a+=+a%5E2-a\" Subtract 'a' from both sides to isolate the a^3 term\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E3+=+a%5E2+-+a\" Simplfy\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E3+=+a-1+-+a\" Replace the \"a%5E2\" with \"a-1\". See equation (1) above.\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E3+=+-1\" Simplify. Note how the 'a' terms on the right side cancel out\r
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\n" ); document.write( "\n" ); document.write( "An alternative is to solve for 'a' using the quadratic formula (after you get everything to one side and have \"a%5E2-a%2B1+=+0\"). That leads to two complex solutions in the form \"a%2Bbi\". After cubing both sides of the two equations you'll lead to \"a%5E3+=+-1\". This method is a lot longer than the first method so I find it ideal to follow the first method. \r
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\n" ); document.write( "\n" ); document.write( "No matter which method you follow, the final answer is -1
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