Originally Posted by

**kenshinofkin** A dealer's profit in units of $5,000 on a new automobile is a random variable X having density function

f(x,y) = 2(1-x) for 0 <= x <= 1 Mr F says: I don't know why you have f(x , **y**) ....?

a) Find the vaiance in the dealer's profit.

b) Demonstrate that chebyshev's inequality holds for k = 2 with the density function above.

[snip]

a) E(2(1-x)) = -4

$\displaystyle \int-1,1 (-2x-1)f(x)dx$ What is f(x) in this problem? (Headbang)

b) How can I show that it holds true?

c) ???