document.write( "Question 1095567: Hi, could you please help me with this question:\r
\n" ); document.write( "\n" ); document.write( "3e^x = 5 + 8e^-x\r
\n" ); document.write( "\n" ); document.write( "- How do you solve for x when the power is negative?
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Algebra.Com's Answer #710074 by ikleyn(52800) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "1.  First step: introduce new variable u = .\r\n" );
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document.write( "    Then your equation takes the form\r\n" );
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document.write( "    3u = 5 + .    (1)\r\n" );
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document.write( "2.  Second step:  multiply by \"u\" both sides:\r\n" );
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document.write( "     3u^2 = 5u + 8,   or\r\n" );
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document.write( "     3u^2 - 5u - 8 = 0.\r\n" );
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document.write( "3.  You got quadratic equation. Its roots are\r\n" );
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document.write( "     =  = .\r\n" );
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document.write( "    a)   =  =  = ;\r\n" );
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document.write( "        ========>   =   ====>  x = .\r\n" );
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document.write( "    b)   =   = -1.\r\n" );
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document.write( "        ========>    = -1   ====> There is NO solution for x.\r\n" );
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document.write( "Answer.  The given equation has a unique solution  x = .\r\n" );
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\n" ); document.write( "\n" ); document.write( "Introducing new variable is the standard method of solving such equations.\r
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