A community for students.
Here's the question you clicked on:
 0 viewing
windsylph
 2 years ago
Probability and Statistics: Let X and Y be independent random variables, and E(A) be the expectation of any random variable A. Simplify this expression: E(2XY  2XE(Y)  2YE(X) + 2E(X)E(Y))
I think it's supposed to be 0, by the way, but I just don't know how this turns out to be 0.
windsylph
 2 years ago
Probability and Statistics: Let X and Y be independent random variables, and E(A) be the expectation of any random variable A. Simplify this expression: E(2XY  2XE(Y)  2YE(X) + 2E(X)E(Y)) I think it's supposed to be 0, by the way, but I just don't know how this turns out to be 0.

This Question is Closed

windsylph
 2 years ago
Best ResponseYou've already chosen the best response.1*please note the correction: E(2XY... instead of E(4XY...

wio
 2 years ago
Best ResponseYou've already chosen the best response.1Do you know about Covariance? Somehow feel this plays a part.

wio
 2 years ago
Best ResponseYou've already chosen the best response.1Well, what formula do you know about covariance that involve the expected value and independent random variables?

windsylph
 2 years ago
Best ResponseYou've already chosen the best response.1Thank you, I just figured out the solution (through looking deeper into covariance). This question is actually part of a larger proof that I'm trying to do, which is the variance of the sum of two independent random variables. I attached the proof, please review it if you wish, for correctness.
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.