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Algebra & Trigonometry with Analytic Geometry

Algebra & Trigonometry with Analytic Geometry

13th Edition

ISBN:9781133382119

Author:Swokowski

Publisher:Swokowski

Chapter10: Sequences, Series, And Probability

Section10.8: Probability

Problem 31E

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Let X₁, X2, X3 be independent & identically distributed
standard normal random variables and let
Y₁ ~ N(1,4) and Y₂ ~ N(0.9) where Y, and Y₂ are
independent & also independent of the Xis, i = 1,2,3.
9.) Give the joint pdf of X₁, X2, X3
b.) What is the variance of ×?
c.) Compute the covariance between
X₁ X₂ +3X3 and 2Y₁ + Y3
-
d). Compute the
X₁ - 12/2X₂ + 3X3
correlation coefficient between
and 2Y₁+ Y3.

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