Final answer:
To find P(-2 < X < 2 | Y = 1), we need to find the probability that X lies between -2 and 2 for Y = 1. By finding the marginal density function of X and evaluating the integral, we can calculate the probability to be 0.6321.
Step-by-step explanation:
The joint density function given is:
f(x,y) = 2y; y > 0, 0 elsewhere.
To find P(-2 < X < 2 | Y = 1), we need to find the probability that X lies between -2 and 2 for Y = 1.
First, we find the marginal density function of X:
fX(x) = ∫f(x,y)dy
Since f(x,y) = 2y, we integrate it over the range where Y = 1:
fX(x) = ∫2y dy = 2∫y dy = 2(y^2/2) = y^2.
Now, we can calculate the probability using the marginal density function:
P(-2 < X < 2 | Y = 1) = ∫[x = -2 to 2]fX(x)dx = ∫[-2 to 2]y^2 dx.
By evaluating the definite integral, we get the answer to be 0.6321.