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# C3 functions

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1. how does this works?

i don't understand why e to the natural log of something is just someting
2. im also doing core 3 but um I think I can explain its like with core 2 where you have an exponential and a log of x they just equal x

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3. well, they are inverse functions of one another so if f(x) =lnx then f^-1(x)= e^x.
and we know that f^-1(f(x)) is always x. or vice versa.
4. They are inverses, so .
Alternatively you can think of it this way. lna is the number that you need to raise e by to get a, so for you are then raising e by this power, so it's a.
5. (Original post by GabbytheGreek_48)
im also doing core 3 but um I think I can explain its like with core 2 where you have an exponential and a log of x they just equal x

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(Original post by nao123)
well, they are inverse functions of one another so if f(x) =lnx then f^-1(x)= e^x.
and we know that f^-1(f(x)) is always x. or vice versa.
(Original post by B_9710)
They are inverses, so .
Alternatively you can think of it this way. lna is the number that you need to raise e by to get a, so for you are then raising e by this power, so it's a.
ah thanks all for explaining
6. no problem Posted from TSR Mobile

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