# Conditional expectations of bivariate normal distributions

#### Ryuuzakie

Hey guys, I'm having a bit of a problem with this question...

1. The problem statement, all variables and given/known data
If X and Y have a bivariate normal distribution with $$m_X=m_y=0$$ and $$\sigma_X=\sigma_Y=1$$, find:

a) E(X|Y=1) and Var(X|Y=1)
b) Pr(X+Y>0.5)

2. Relevant equations
N/A

3. The attempt at a solution
Apologies, but I don't seem to know where to start on this one.

Related Calculus and Beyond Homework News on Phys.org

#### lanedance

Homework Helper
how about the joint denisty function?

Homework Helper

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