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c3 exp

2e^2x=e^x-2 show how to get this value please:redface:
Make the substitution u=exu=e^x and solve a quadratic equation.
Reply 2
2e^2x=e^(x-2)

sorry but if that was the case i would of done it i wrote it wrong
Reply 3
Take ln of both sides to start off with.
Reply 4
Original post by Secreay
2e^2x=e^(x-2)

sorry but if that was the case i would of done it i wrote it wrong


2e2x=ex2[br]2e2x=exe2[br]2e2x=exe2[br]2e2xe2=ex[br][br] \displaystyle 2e^{2x}=e^{x-2}[br]\displaystyle 2e^{2x}=e^xe^{-2} [br]\displaystyle 2e^{2x}= \frac{e^x}{e^2}[br]\displaystyle 2e^{2x}e^2=e^x[br][br]

Can you complete it?
Reply 5
Original post by Secreay
2e^2x=e^x-2 show how to get this value please:redface:


Is it 2e^(2x)=e^(x-2) or 2e^(2x)=(e^x)-2 or something else
Original post by Secreay
2e^2x=e^(x-2)

sorry but if that was the case i would of done it i wrote it wrong


Make the equation equal to zero and factorise exe^x.
Reply 7
If you don't like factorising quadratics you could go this way:

2e^(2x) = e^(x-2)
2 X e^x X e^x = e^x X e^-2
2 X e^x = e^-2
e^x = 1/2 e^-2
x = ln (1/2 e^-2)

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