Suppose that {Yt } is stationary with autocovariance function γk. (a) Show that Wt = ∇Yt = Yt − Yt − 1 is stationary by finding the mean and autocovariance function for {Wt }. (b) Show that Ut = ∇2Yt = ∇[Yt − Yt−1] = Yt − 2Yt−1 + Yt−2 is stationary. (You need not find the mean and autocovariance function for {Ut }.)

lol we need to see what the question is asking about

step-by-step explanation:

step-by-step explanation:

use pothagarean therom

a^2+b^2=c^2 so first ac

acm is a right triangle because c= 90°

and am (the hypotenuse or c) =16+9 =25

but there is not enough info we need another angle or side length

he kicked it up? is this the answer ?

step-by-step explanation:

add a pic of the graph, then ill edit this "answer" and solve it for you : 3

step-by-step explanation: