Re: [理工] [機率]-pdf的問題
※ 引述《fairwarning (一輪明月與藍夜!!)》之銘言：
: [題目]
: x , 0 < x <= 1
: 若 r.v.X 其pdf f (x) = 2-x , 1 <= x < 2 試求 F(x)
: X 0 , elsewhere X
: [解答]
: 0 , x < 0
: F(x) = (x^2)/2 , 0 <= x < 1
: X -1+2x-[(x^2)/2] , 1 <= x < 2
: 1 , 2 <= x
: 請問大家...
: 請問解答怎麼來的呢?
: 個人想法..
: 解答的0與1是因為 0 <= F(x,y) <= 1 嗎?
: XY
: 可以請大家幫幫我嗎?
: 初接觸通訊 很不熟析...
: 在此先謝謝大家的幫忙喔 謝謝
-∞
∫ 0 dx=0 ; x<0
0
x |x=x
∫ x dx=0.5x^2| =0.5 x^2
0 |x=0 ;0=<x<1
x |x=x
∫ 2-x dx=2x-0.5x^2| =(2x-0.5x^2)-(2-0.5) =-0.5x^2+2x-1.5 ;1=<x<2
1 |x=1
∞
∫ 0 dx =0 ;2=<x
2
--
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◆ From: 115.165.242.132
推
07/29 17:32, , 1F
07/29 17:32, 1F
→
07/29 17:34, , 2F
07/29 17:34, 2F
→
07/29 17:34, , 3F
07/29 17:34, 3F
→
07/29 17:35, , 4F
07/29 17:35, 4F
推
07/29 17:36, , 5F
07/29 17:36, 5F
→
07/29 17:36, , 6F
07/29 17:36, 6F
→
07/29 17:37, , 7F
07/29 17:37, 7F
→
07/29 17:38, , 8F
07/29 17:38, 8F
推
07/29 17:40, , 9F
07/29 17:40, 9F
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