1( = @ 1( > 2( > 3( 4( > 2( 45 % @ @ > > > @ > > = > 1( 180 2( 162 3 ...

126+∞2E(X) = ∫ xf (x)dx ⇒ E( x ) = ∫−∞0233 ⎤1 2 1 1 + 1⎥= ∫ x 2dx= × x 2 =2 2 3⎥0+ 1 ⎥2 ⎦0P( X1 ⎡11 ⎤==2 ⎢− ( − )3 3 ⎥⎣ ⎦13152xf (x)dx = ∫052⎤x 2 ⎥ =⎥⎦01 11 1 1 3 3 1< ) = P( − < x < ) = ∫ f (x)dx = ∫ (3 3 3 1 1− −2 )dx3 3452. 4 (15xx ( )dx2. 3 (16ρ =Cov(x, y)δ x δ yρ (ax + b,ey + d) =− 2 2= = −2/5×2 5P( ) = 1− P(ρ(x, y) . 2 (17 . 3 (18 )⎡ 3 ⎛10⎞1 0 4i0 6n i ⎤− ⎢ ⎜ ⎟ / /−⎥ = 1−0/3823 = 0/6177⎣i=0⎝i⎠ ⎦= ∑Var (x) = npq = 10 × 0/4×0/6 = 2/4. 1 (19. 2 (2013 −12P (x > 3 ) = P(z > ) = P(z > 0/67)= 1−φ0/66 = 1−0/745 = 0/2551/5