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dcfcviper
Nov 1, 2007, 06:07 AM
Hi,

I'm stuck with the following problem and need some help.

3(e^6x - 8e^3x) = -9

I've tried it two way and got the same wrong answer so any pointers towards the right one will be much appreciated :)

ebaines
Nov 1, 2007, 06:19 AM
Notice that e^6x is equal to (e^3x)^2. So you can express the problem as a quadratic equation, and use the quadratic formula to solve for e^3x. Does this help?

dcfcviper
Nov 1, 2007, 06:23 AM
No, I already tried that. Maybe my I made an error in the calculation then.

ebaines
Nov 1, 2007, 06:36 AM
No, I already tried that. Maybe my I made an error in the calculation then.

Try it again - it worked for me! What answer are you getting?

dcfcviper
Nov 1, 2007, 06:39 AM
Tried it again and got it now, thanks a lot :thup:

Must have missed something when doing it last night, had already done a fair bit of maths when trying to do this so was probably tired.

Thanks again.