document.write( "Question 883678: The curve y = e^x + 4e^-2x has one stationary point.\r
\n" ); document.write( "\n" ); document.write( "Find the x-coordinate of this point
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Algebra.Com's Answer #533691 by rothauserc(4718)\"\" \"About 
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We find the stationary point by finding dy/dx and setting the result to 0 and solving for x
\n" ); document.write( "note that dy/dx of e^x is e^x and dy/dx of e^-2x is e^-2x, therefore
\n" ); document.write( "dy/dx of e^x + 4e^-2x is e^x -8e^-2x
\n" ); document.write( "now let's set it = 0
\n" ); document.write( "e^x -8e^-2x = 0 then
\n" ); document.write( "e*x = 8/e^2x
\n" ); document.write( "multiply both sides of = by e^2x
\n" ); document.write( "e^3x = 8
\n" ); document.write( "use definition of logarithms
\n" ); document.write( "3x = ln 8
\n" ); document.write( "3x = 2.07944154
\n" ); document.write( "x = 0.69314718
\n" ); document.write( "this is the x co-ordinate of the stationary point\r
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