document.write( "Question 957761: Either factor or use the quadratic formula to solve the given equation. (Enter your answers as a comma-separated list.)
\n" ); document.write( "(ln x)^2 + 2 ln x = 3
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Algebra.Com's Answer #585294 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
sometimes it helps to make your expression equal to a variable so the process of factoring doesn't look so messy.\r
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\n" ); document.write( "\n" ); document.write( "if you let y = ln(x), then your equation becomes:\r
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\n" ); document.write( "\n" ); document.write( "y^2 + 2y = 3\r
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\n" ); document.write( "\n" ); document.write( "subtract 3 from both sides to get:\r
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\n" ); document.write( "\n" ); document.write( "y^2 + 2y - 3 = 0\r
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\n" ); document.write( "\n" ); document.write( "the equation is now in standard form of ay^2 + by + c = 0, where:\r
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\n" ); document.write( "\n" ); document.write( "a = 1
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\n" ); document.write( "c = -3\r
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\n" ); document.write( "\n" ); document.write( "this allows you to use the quadratic formula if you need it.\r
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\n" ); document.write( "\n" ); document.write( "in this case you don't need it because the equation can be factored manually.\r
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\n" ); document.write( "\n" ); document.write( "this equation can be factored as (y+3) * (y-1) = 0\r
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\n" ); document.write( "\n" ); document.write( "set each of these factors to 0 and you get (y+3) = 0 and (y-1) = 0\r
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\n" ); document.write( "\n" ); document.write( "solve for y to get y = -3 and y = 1\r
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\n" ); document.write( "\n" ); document.write( "replace y with ln(x) that you made it equal to in the beginning.\r
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\n" ); document.write( "\n" ); document.write( "y = -3 becomes ln(x) = -3\r
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\n" ); document.write( "\n" ); document.write( "y = 1 becomes ln(x) = 1\r
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\n" ); document.write( "\n" ); document.write( "solve for x in each of these equations.\r
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\n" ); document.write( "\n" ); document.write( "ln(x) = -3 if and only if e^(-3) = x which results in x = .0497870684.\r
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\n" ); document.write( "\n" ); document.write( "ln(x) = 1 if and only if e^1 = x which results in x = 2.718281828.\r
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\n" ); document.write( "\n" ); document.write( "replace each of these values for x in the original equation to see if those original equations hold true.\r
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\n" ); document.write( "\n" ); document.write( "the original equation is ln(x)^2 + 2*ln(x) = 3\r
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\n" ); document.write( "\n" ); document.write( "replace x with .0497870684 and you get ln(x)^2 + 2*ln(x) = 3 becomes 3 = 3.\r
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\n" ); document.write( "\n" ); document.write( "replace x with 2.718281828 and you get ln(x)^2 + 2*ln(x) = 3 becomes 3 = 3.\r
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\n" ); document.write( "\n" ); document.write( "both values of x are good so they are your solutions.\r
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