document.write( "Question 209731: i worked this problem like this:
\n" ); document.write( "e^2x - 3e^x + 2 = 0
\n" ); document.write( "e^2x - 3e^x = -2
\n" ); document.write( "e^(2x\x^3) = e^(-2)
\n" ); document.write( "(2\x^2)= e^(-2)
\n" ); document.write( "2= e^(-2x^2)
\n" ); document.write( "(2\e^-2) = x^2
\n" ); document.write( "sqrt(14.778)= sqrt(x^2)
\n" ); document.write( "x=3.844\r
\n" ); document.write( "\n" ); document.write( "i tried my answer. but it doesnt work out.
\n" ); document.write( "what did i do wrong?
\n" ); document.write( "thanks in advance
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #158587 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
\"e%5E%282x%29+-+3e%5Ex+%2B+2+=+0\"
\n" ); document.write( "\"e%5E%282x%29+-+3e%5Ex+=+-2\"
\n" ); document.write( "Not wrong, but doesn't help.
\n" ); document.write( "e^((2x)/(x^3)) = e^(-2)
\n" ); document.write( "???! There is no way to arrive at this statement from the previous one.

\n" ); document.write( "The key to solving the equation, \"e%5E%282x%29+-+3e%5Ex+%2B+2+=+0\", is to recognize that
  • \"e%5E%282x%29+=+%28e%5Ex%29%5E2\"
  • the equation can then be written as: \"%28e%5Ex%29%5E2+-+3e%5Ex+%2B+2+=+0\"
  • the equation is therefore a quadratic equation in \"e%5Ex\"

\n" ); document.write( "If you have trouble seeing the last two, we can use a substitution to make it clearer. Let \"q+=+e%5Ex\". Replacing \"e%5Ex\" with q we get:
\n" ); document.write( "\"q%5E2+-+3q+%2B+2+=+0\".

\n" ); document.write( "We can solve this for q (aka \"e%5Ex\") with the quadratic formula or by factoring:
\n" ); document.write( "\"%28q+-+2%29%28q+-+1%29+=+0\"
\n" ); document.write( "In order for this product to be zero, one of the factors must be zero:
\n" ); document.write( "\"q+-+2+=+0\" or \"q+-+1+=+0\"
\n" ); document.write( "Solving these we get:
\n" ); document.write( "\"q+=+2\" or \"q+=+1\"
\n" ); document.write( "Of course we are not interested in \"q\". We are interested in \"x\". So we can substitute back in for \"q\":
\n" ); document.write( "\"e%5Ex+=+2\" or \"e%5Ex+=+1\"
\n" ); document.write( "To solve these for x we will find the natural log of each side:
\n" ); document.write( "\"ln%28e%5Ex%29+=+ln%282%29\" or \"ln%28e%5Ex%29+=+ln%281%29\"
\n" ); document.write( "Using one of the properties of logarithms: \"log%28a%2C+%28x%5Ey%29%29+=+y%2Alog%28a%2C+x%29\" we get:
\n" ); document.write( "x*ln(e) = ln(2) or x*ln(e) = ln(1)
\n" ); document.write( "Since the ln(e) is 1 by definition and ln(1) is zero:
\n" ); document.write( "x = ln(2) or x = 0
\n" ); document.write( "
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