document.write( "Question 142982: For the following, solve. Find exact solutions\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E4-3y%5E2=-1\"
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Algebra.Com's Answer #104029 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"y%5E4-3y%5E2=-1\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E4-3y%5E2%2B1=0\" Add 1 to both sides\r
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\n" ); document.write( "\n" ); document.write( "Let \"x=y%5E2\". So this means that \"x%5E2=y%5E4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-3x%2B1=0\" Replace \"y%5E4\" with \"x%5E2\". Replace \"y%5E2\" with \"x\". \r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"x%5E2-3%2Ax%2B1=0\" ( notice \"a=1\", \"b=-3\", and \"c=1\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A1+%29%29%2F%282%2A1%29\" Plug in a=1, b=-3, and c=1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A1+%29%29%2F%282%2A1%29\" Negate -3 to get 3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9-4%2A1%2A1+%29%29%2F%282%2A1%29\" Square -3 to get 9 (note: remember when you square -3, you must square the negative as well. This is because \"%28-3%29%5E2=-3%2A-3=9\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9%2B-4+%29%29%2F%282%2A1%29\" Multiply \"-4%2A1%2A1\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+5+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%285%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%285%29%29%2F2\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B+sqrt%285%29%29%2F2\" or \"x+=+%283+-+sqrt%285%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "So the solutions in terms of x are\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B+sqrt%285%29%29%2F2\" or \"x+=+%283+-+sqrt%285%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "But remember, we let \"x=y%5E2\". So this means \r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2+=+%283+%2B+sqrt%285%29%29%2F2\" or \"y%5E2+=+%283+-+sqrt%285%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Take the square root of both sides in each case\r
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\n" ); document.write( "\n" ); document.write( "\"y+=0%2B-sqrt%28+%283+%2B+sqrt%285%29%29%2F2%29\" or \"y+=0%2B-sqrt%28+%283+-+sqrt%285%29%29%2F2%29\"\r
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\n" ); document.write( "\n" ); document.write( "So after breaking up the expressions, we get the four solutions\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+sqrt%28+%283+%2B+sqrt%285%29%29%2F2%29\", \"y+=+-sqrt%28+%283+%2B+sqrt%285%29%29%2F2%29\", \"y+=sqrt%28+%283+-+sqrt%285%29%29%2F2%29\", \"y+=-sqrt%28+%283+-+sqrt%285%29%29%2F2%29\"
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