# Math Help - Joint Density Problem Help!

1. ## Joint Density Problem Help!

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2. $E(Y_1)=\int_0^1\int_0^1 y_1f(y_1,y_2)dy_1dy_2$

$E(Y^2_1)=\int_0^1\int_0^1 y_1^2f(y_1,y_2)dy_1dy_2$

$E(Y_2)=\int_0^1\int_0^1 y_2f(y_1,y_2)dy_1dy_2$

$E(Y_2^2)=\int_0^1\int_0^1 y_2^2f(y_1,y_2)dy_1dy_2$

$E(Y_1Y_2)=\int_0^1\int_0^1 y_1y_2f(y_1,y_2)dy_1dy_2$

$V(X)=E(X^2)-(E(X))^2$

3. Thanks, but im still confuse about solving (b) and (c) for the equation you gave me.

4. I didn't do (c).
I'm waiting for you to show some of your work from (a) and (b).

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6. you need to review calc 1

$\int xdx={x^2\over 2} +C$ and $\int x^2dx={x^3\over 3} +C$

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