Let random variable be $X\sim U([-2,2])$, random variable $Y=5X-4$.
Calculate $EY$ and $D^{2}Y$
D-variance
My take:
$EX=-2$
$D^{2}X$= 4
$EY=E(5x-4)=5EX-4=5*(-2)-4=-14$
$D^{2}Y=D^{2}(5X-4)=25D^{2}X=25*4=100$
Could anyone check if my answers are correct?
@Edit
$EX=0$
$D^{2}X$= 4
$EY=E(5x-4)=5EX-4=5*0-4=-4$
$D^{2}Y=D^{2}(5X-4)=25D^{2}X=25*4=100$
The expectation is right, but $Var(X) = \frac {16}{12}= \frac {4}{3} $ and then $Var(Y) = 25*Var(X)= 33.333 $