document.write( "Question 462550: find all real solutions of the equations : (x^2 +1)^2 - 18( x^2 +1) = -17 \n" ); document.write( "
Algebra.Com's Answer #317083 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
\"%28x%5E2+%2B1%29%5E2+-+18%28+x%5E2+%2B1%29+=+-17\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E4%2B2x%5E2+%2B1+-+18x%5E2+-1+=+-17\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E4+-16x%5E2+%2B17=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%29%5E2+-16x%5E2+%2B17=0\"...you can solve it as quadratic using quadratic formula, you will just have four solutions; both solutions as quadratic equation you will take positive i negative value of their square root\r
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2-16%2Ax%2B17=0\" ( notice \"a=1\", \"b=-16\", and \"c=17\")
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\n" ); document.write( " \"x+=+%28--16+%2B-+sqrt%28+%28-16%29%5E2-4%2A1%2A17+%29%29%2F%282%2A1%29\" Plug in a=1, b=-16, and c=17
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\n" ); document.write( " \"x+=+%2816+%2B-+sqrt%28+%28-16%29%5E2-4%2A1%2A17+%29%29%2F%282%2A1%29\" Negate -16 to get 16
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\n" ); document.write( " \"x+=+%2816+%2B-+sqrt%28+256-4%2A1%2A17+%29%29%2F%282%2A1%29\" Square -16 to get 256 (note: remember when you square -16, you must square the negative as well. This is because \"%28-16%29%5E2=-16%2A-16=256\".)
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\n" ); document.write( " \"x+=+%2816+%2B-+sqrt%28+256%2B-68+%29%29%2F%282%2A1%29\" Multiply \"-4%2A17%2A1\" to get \"-68\"
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\n" ); document.write( " \"x+=+%2816+%2B-+sqrt%28+188+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%2816+%2B-+2%2Asqrt%2847%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%2816+%2B-+2%2Asqrt%2847%29%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%2816+%2B+2%2Asqrt%2847%29%29%2F2\" or \"x+=+%2816+-+2%2Asqrt%2847%29%29%2F2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=%2B16%2F2%2B2%2Asqrt%2847%29%2F2\" or \"x=%2B16%2F2-2%2Asqrt%2847%29%2F2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=8%2Bsqrt%2847%29\" or \"x=8-sqrt%2847%29\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=8%2Bsqrt%2847%29\" or \"x=8-sqrt%2847%29\"
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\n" ); document.write( "So yoursolutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=sqrt%288%2B%28sqrt%2847%29%29%29+\" or \"x=sqrt%288-%28sqrt%2847%29%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=sqrt%288%2B6.8556546%29+\" or \"x=sqrt%288-6.8556546%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=sqrt%2814.8556546%29+\" or \"x=sqrt%281.1443454%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=3.8543\" or \"x=1.06974\"\r
\n" ); document.write( "\n" ); document.write( "so, your solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=3.8543\"
\n" ); document.write( "\"x=-3.8543\"
\n" ); document.write( "\"x=1.06974\"
\n" ); document.write( "\"x=-1.06974\"\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-5%2C+40%2C+-20%2C+40%2C+x%5E4+-16x%5E2+%2B17%29+\"
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