document.write( "Question 370127: I've been stuck on this problem for a really long time. I'm trying to figure out a problem reducible to a quadratic equation in a step by step method so I can understand how I get from one point to the other. \r
\n" ); document.write( "\n" ); document.write( "The problem is: w^4-6w^2-2=0
\n" ); document.write( "I only know this:\r
\n" ); document.write( "\n" ); document.write( "u = w^2\r
\n" ); document.write( "\n" ); document.write( "From my text and all the research I've done, I also know that I would rewrite this problem as:\r
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\n" ); document.write( "\n" ); document.write( "u^2 - 6u - 2 = 0\r
\n" ); document.write( "\n" ); document.write( "I have to solve this but it's not factorable which is where I am absolutely stumped. This is an example problem on my homework I'm providing here so I have the answers for that but I just don't know how they got them.\r
\n" ); document.write( "\n" ); document.write( "This is the way they worked it out.....\r
\n" ); document.write( "\n" ); document.write( "u^2-6u-2=0
\n" ); document.write( "they solve for u...but how????\r
\n" ); document.write( "\n" ); document.write( "they got the answer
\n" ); document.write( "u=3-sqrt11 or u=3+sqrt11\r
\n" ); document.write( "\n" ); document.write( "then after this the problem needs to be solved for w.\r
\n" ); document.write( "\n" ); document.write( "Is there any way you can help and show me in a step by step fashion so I get this? Thank you. LeAnn
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Algebra.Com's Answer #263779 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
You found that \"u=3-sqrt%2811%29\" or \"u=3%2Bsqrt%2811%29\", which is completely correct. However, we want to solve for 'w'.\r
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\n" ); document.write( "\n" ); document.write( "Recall that you let \"u=w%5E2\". \r
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\n" ); document.write( "\n" ); document.write( "So plug this into the two equations above to get\r
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\n" ); document.write( "\n" ); document.write( "\"w%5E2=3-sqrt%2811%29\" or \"w%5E2=3%2Bsqrt%2811%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now we need to solve each equation for 'w'. We'll do this by taking the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "So solve \"w%5E2=3-sqrt%2811%29\" for w to get\r
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\n" ); document.write( "\n" ); document.write( "\"w=sqrt%283-sqrt%2811%29%29\" or \"w=-sqrt%283-sqrt%2811%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now solve \"w%5E2=3%2Bsqrt%2811%29\" for w to get\r
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\n" ); document.write( "\n" ); document.write( "\"w=sqrt%283%2Bsqrt%2811%29%29\" or \"w=-sqrt%283%2Bsqrt%2811%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "So the four solutions are \r
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\n" ); document.write( "\n" ); document.write( "\"w=sqrt%283-sqrt%2811%29%29\", \"w=-sqrt%283-sqrt%2811%29%29\", \"w=sqrt%283%2Bsqrt%2811%29%29\", or \"w=-sqrt%283%2Bsqrt%2811%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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