Log/matrix/calc/algebra/probability/retarded question.

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Homework Help Overview

The discussion revolves around a complex exercise that integrates concepts from logarithms, matrices, calculus, and probability. The original poster expresses confusion regarding specific components of the problem, particularly in relation to the notation and the interpretation of certain mathematical expressions.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants explore the meaning of absolute value signs in the context of logarithms and question the necessity of these signs. There is also discussion about the definitions of probability notations, particularly Pr(A) and Pr(A'), and how they relate to the overall problem. The interpretation of derivatives and their evaluation points is also debated.

Discussion Status

Participants are actively engaging with the problem, offering insights and clarifications about the mathematical concepts involved. Some guidance has been provided regarding the interpretation of logarithmic expressions and probability, but there remains a lack of consensus on certain aspects of the problem, particularly the evaluation of derivatives.

Contextual Notes

There is mention of the exercise being an extended-response type, which may impose additional constraints on how the problem is approached. The original poster indicates uncertainty about the clarity of the problem setup, particularly with the graphical representation used.

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Homework Statement



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The Attempt at a Solution



This is a really strange question. It's an extended-response exercise. I don't think it'd look pretty using the TeX thing, so I drew it in Paint. It combines all the topics we've done so far. Row 1 is easy. Row 2, column 1, I have no clue how to do. I'm not sure about the straight lines on the log in the bottom right, either.

http://img260.imageshack.us/img260/9584/blahgm8.png
 
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In A22, the vertical lines are absolute value signs, which basically means that you take the positive value of what's inside them. In general, these are needed since the logarithm function is only defined for postiive real numbers. However, in this case, the argument is positive, and they are not really needed.

For A21, I'm afraid I don't really know what the Pr(A) and Pr(A') means. [Do you have the definition of Pr(A')? It looks like it must be equal to -Pr(A)]
 
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Pr(A) and Pr(A'), I'm sure, are "Probabiliity that event A occurs" and "Probability even A does not occur". It's a bit annoying that they also use A to represent the entire matrix, but, hey, it's a silly exercise to begin with! Whatever "event A" is, Pr(A)+ Pr(A') is easy trivial!

Oh, and for A22 use the obvious loge ex= x.

The problem I have is A21:
[tex]\left(\frac{d}{dx}(x^2)\right)^0[/tex]

I would interpret that as the derivative evaluated at x= 0 but then the answer is not what you give! The derivative evaluated at x= 1/2 will give that answer.

Finally, this is surely not "precalculus"!
 
I'm pretty sure that's "raised to the 0-th power".
 
Ah, that makes sense!
 
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Ah, I see, so the probabilities added up is 1?
 
Yes, of course.
 

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