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Maths logs and exponentials problem

the question this is regarding is:

solve e^lnx + lne^x=8

I am confused as to whether to log both sides or inverse both sides. How do you know which one to use?
Original post by epic08
the question this is regarding is:

solve e^lnx + lne^x=8

I am confused as to whether to log both sides or inverse both sides. How do you know which one to use?


Take a step back, and think about how you can simplify each of the two terms on the left hand side.
Reply 2
Ok so i decided to try using inverse

so it became lne^lnx +ln^2e^x = 8

I took lne^lnx and split it into lnx x lne
lne is 1 so that leaves lnx x 1 = lnx
Reply 3
Original post by 15Characters...
Take a step back, and think about how you can simplify each of the two terms on the left hand side.

I don't see how I can simplify it?
Original post by epic08
I don't see how I can simplify it?

You can simplify each of the two terms individually. For example, what is lnex\ln e^x?
Reply 5
Original post by 15Characters...
You can simplify each of the two terms individually. For example, what is lnex\ln e^x?

lne^x = x

e^lnx = x

x+x = 2x
2x = 8
x=4

Ok, I was majorly over complicating that thank you.
Original post by epic08
lne^x = x

e^lnx = x

x+x = 2x
2x = 8
x=4

Ok, I was majorly over complicating that thank you.

Great!

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