document.write( "Question 63903: Solve for x: e^2x + 4e^-2x = 4.\r
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document.write( "a. (1/2) ln 2
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document.write( "b. (1/3) ln 2
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document.write( "c. (1/3) ln 3
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document.write( "d. (1/2) ln 3
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document.write( "e. ln 2
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document.write( "f. ln 3
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document.write( "g. none of these \n" );
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Algebra.Com's Answer #44544 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! e^2x + 4e^-2x = 4 \n" ); document.write( "Multiply thru by e^(2x) to get: \n" ); document.write( "e^4x + 4 = 4e^2x \n" ); document.write( "Rewrite as: \n" ); document.write( "(e^2x)^2-4(e^2x)+4=0 \n" ); document.write( "This is a quadratic with variable e^2x. \n" ); document.write( "Let e^2x=w, then rewrite the equation as: \n" ); document.write( "w^2-4w+4=0 \n" ); document.write( "(w-2)^2=0 \n" ); document.write( "w=2 \n" ); document.write( "Therefore e^2x=2 \n" ); document.write( "Take the natural law of both sides to get: \n" ); document.write( "2x=ln2 \n" ); document.write( "x=(1/2)ln2 \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |