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# S2 pdf help Watch

1. f(x) =
$\frac{1}{3}(1+\frac{x}{2})$ $0\leq x\leq 2$
0 otherwise

How do you find E(3X+2) and Var(3X+2)
2. Bit rusty on S2 but I think you just find E(X) and Var(X) through integration, then use the following rules:

E(aX+b) = aE(X) + b
Var(aX+b) = a^2(Var(X))
3. (Original post by Graph)
Bit rusty on S2 but I think you just find E(X) and Var(X) through integration, then use the following rules:

E(aX+b) = aE(X) + b
Var(aX+b) = a^2(Var(X))
Thanks
4. I'm just here for reps

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