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karnten07
Feb19-08, 06:30 PM
1. The problem statement, all variables and given/known data
Im doing a problem where im trying to show that an abelian group with a scalar multiplication is a vector field. Im trying to show associativity right now and just have a question:

im trying to show that exp(b.c.lnx) = b.exp(c.lnx)

But im not very sure of my logs and exp's laws, not sure that they are even equal. Any pointers guys?


2. Relevant equations



3. The attempt at a solution

foxjwill
Feb19-08, 08:12 PM
They wouldn't be equal.

Since e^x and \ln x are inverses of each other, e^{\ln x} = x. Therefore, your expressions can be simplified to x^{bc} = bx^c which are not equal.

Also, a simple counter-example shows the same result: Taking x=3, b=2, c=1 we have 3^{1\cdot 2}=2\cdot 3^1 which is obviously not true.