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Exponential question (1 Viewer)

Aysce

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Solve for x:

e^x - 2e^x - 4 = 0

I know this is a reducible quadratic but I don't know what to do when trying to solve for x when I factorise the equation
 

krnofdrg

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let ex=m

ex-2ex-4=0 (the root x)

m-2m-4=0

Use quadratic formula.

Once you find the m values. then re-sub e^x and to your ms and solve equations like that
Do it for both m s
 

Aysce

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I did it that way but it comes with e^x = 1 +- (5)^0.5
Sorry on my phone, and says that answer is 0.
 

SpiralFlex

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Solve for x:

e^x - 2e^x - 4 = 0

I know this is a reducible quadratic but I don't know what to do when trying to solve for x when I factorise the equation
Assuming there is no typo.

Not possible. However if you meant,



Let









Remember our inverse functions,



But is not possible since the natural logarithm is only defined for a domain of .
 
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Aysce

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Thanks yeah twas a typo.
 

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