Natural Log of Product Solution

Phox
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Homework Statement



L(θ) = ∏(θ/(2√xi)*e^(-θ√xi)),i=1, n

Homework Equations





The Attempt at a Solution



-> θ2∏(1/(2√xi)*e^(-θ√xi))

taking natural log of both sides

lnL(θ) = nlnθ + ln∏(1/(2√xi)*e^(-θ√xi))

= nlnθ + Ʃln(1/(2√xi)*e^(-θ√xi))

Ok so from what I understand the ln of a product is the sum. But I'm not sure how exactly to simplify from here
 
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Phox said:
= nlnθ + Ʃln(1/(2√xi)*e^(-θ√xi))

Ok so from what I understand the ln of a product is the sum.
You can apply that again to the product [1/(2√xi)]*[e^(-θ√xi)]. You can then also use ln(xa) = a ln(x) for cases like a = -1, a = 1/2. What can you do with ln(ex)?
 
Phox said:

Homework Statement



L(θ) = ∏(θ/(2√xi)*e^(-θ√xi)),i=1, n

Homework Equations


The Attempt at a Solution



-> θ2∏(1/(2√xi)*e^(-θ√xi))

taking natural log of both sides

lnL(θ) = nlnθ + ln∏(1/(2√xi)*e^(-θ√xi))

= nlnθ + Ʃln(1/(2√xi)*e^(-θ√xi))

Ok so from what I understand the ln of a product is the sum. But I'm not sure how exactly to simplify from here

##ln(\frac{a}{b}) = ln(a) - ln(b)##
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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