document.write( "Question 758391: solve for x\r
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Algebra.Com's Answer #461449 by lwsshak3(11628) $\"\"$ $\"About$

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solve for x
\n" ); document.write( "e^2x - 2e^x - 8 = 0
\n" ); document.write( "let u=e^x
\n" ); document.write( "u^2=e^2x
\n" ); document.write( "u^2-2u-8=0
\n" ); document.write( "(u-4)(u+2)=0
\n" ); document.write( "u=-2=e^x
\n" ); document.write( "e^x=-2 (reject, e^x>0)
\n" ); document.write( "or
\n" ); document.write( "u=4=e^x
\n" ); document.write( "e^x=4
\n" ); document.write( "xlne=ln4
\n" ); document.write( "x=ln4≈1.3863..
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