A PDF formed from a multivariate function

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Homework Help Overview

The discussion revolves around the formation of a probability density function from a bivariate function. The original poster presents a problem involving the calculation of specific values and statistical measures related to the function.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to substitute values into the probability density function and integrate it to find necessary parameters. They express difficulty with a calculator error and seek advice on how to proceed.

Discussion Status

Participants are engaged in clarifying the nature of the error encountered by the original poster. Suggestions for simplifying the function or using alternative tools have been offered, indicating a collaborative exploration of potential solutions.

Contextual Notes

The discussion highlights a specific error message related to memory limitations on the calculator, which may impact the ability to perform the required calculations. The original poster's approach involves multiple steps that depend on accurate integration and substitution.

Saracen Rue
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Homework Statement


A probability density function, ##p\left(x\right)=\int _{-a}^a\left(f\left(x,\left(a-y\right)\right)-f\left(y,ax\right)\right)dy##, can be formed from the bivariate function ##f\left(x,y\right)=y\sqrt{\left(x-2\right)^2-y}## over the domain ##[0,b]## - where ##b## is the coordinate of the x-intercept.

(a) Determine the values of ##a## and ##b## correct to 5 decimal places
(b) Calculate the expected value, variance and standard deviation of ##p(x)## correct to 4 decimal places
(c) Find the percentage probability of the continuous random variable ##X## being withing ##|a|## standard deviations either side of the mean​

Homework Equations


Knowledge or probability density functions, including integral applications.

The Attempt at a Solution


Well I know that I need to substitute the actual values for ##f\left(x,\left(a-y\right)\right)## and ##f\left(y,ax\right)## into ##p(x)## to be able to integrate ##\int _{-a}^a\left(f\left(x,\left(a-y\right)\right)-f\left(y,ax\right)\right)dy##, and then I'd need to solve ##int_0^b p(x)dx for b and then use that to solve for a. However, when I attempt to do this on my calculator I receive and error message. Does anyone know how I could do this?
 
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Which error message do you get?
 
mfb said:
Which error message do you get?

I receive the message: "ERROR: Insufficient Memory"
 
Maybe you can simplify the function a bit, or use a better calculator.
 

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