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# intergrate e watch

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1. what do i gte if i intergrate e^x ? i know its something easy but ive forgotten and its not in my books!

thanks
2. It's just e^x again

However the integral of e^kx = (1/k)e^kx

(the 'k' in e^x is 1, so that's why you just get e^x when integrated)
3. (Original post by mockel)
It's just e^x again

However the integral of e^kx = (1/k)e^kx

(the 'k' in e^x is 1, so that's why you just get e^x when integrated)

hmmmm ok im trying to show that f(t)=0.1e^-0.1t for t>= 0 is a properly defined probability distribution so do i intergrate to infinity and get

0.1[-1/0.1 e^-0.1t] from zero to infinity?
4. Well, I don't know about the statistics 'background' but the integral looks fine to me, and it'll simplify to:

-e^(-0.1t) (+ C ?)
5. (Original post by sarah12345)
hmmmm ok im trying to show that f(t)=0.1e^-0.1t for t>= 0 is a properly defined probability distribution so do i intergrate to infinity and get

0.1[-1/0.1 e^-0.1t] from zero to infinity?
INT[0.1exp(0.1t)] = -exp(-0.1t) [between 0 and infinity]

Lim(t->infinity) [-exp(-0.1t)] = 0

So integral is (0 - (-1)) = 1, hence it's a valid probability distribution as it integrates to one over all x > 0 values.

Euclid.

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