Exercises 1. Suppose that X1 and X2 are random variables with zero mean and unit variance. If the correlation coefficient of X1 and X2 is -0.5, then what is the variance of Y =- k² Xk ? %3D 2. If the joint density of the random variables X and Y is if (x, y) E { (x, 0), (0, -y)|x, y = -2, – 1, 1,2} f(r, y) otherwise, 1/8

Exercises 1. Suppose that X1 and X2 are random variables with zero mean and unit variance. If the correlation coefficient of X1 and X2 is -0.5, then what is the variance of Y =- k² Xk ? %3D 2. If the joint density of the random variables X and Y is if (x, y) E { (x, 0), (0, -y)|x, y = -2, – 1, 1,2} f(r, y) otherwise, 1/8

Algebra & Trigonometry with Analytic Geometry

13th Edition

ISBN:9781133382119

Author:Swokowski

Publisher:Swokowski

Chapter10: Sequences, Series, And Probability

Section10.8: Probability

Problem 20E

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Question

Exercises
1. Suppose that X1 and X2 are random variables with zero mean and unit
variance. If the correlation coefficient of X1 and X2 is -0.5, then what is the
variance of Y ='E- k2 Xk ?
乙k=1
2. If the joint density of the random variables X and Y is
if (x, y) E { (x,0), (0,-y)|x, y = -2, -1, 1,2}
f(x, y) :
0.
otherwise,

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