... thổùc - - 25 - Chổồng II- 9/15/ 2 25. Haỡm CDF cỏỳp 2 vaỡ haỡm PDF cỏỳp 2 lỏửn lổồỹt laỡ: {} 21 21 2 12 2 121 2 22 1 121 2 12 xx)t,t,x,x(F)t,t,x,x(fx)t(,x)t(p)t,t,x,x(F== 26 . Mọỹt sọỳ ... õóỳn N = 2 laỡ õuớ. Khi N = 2 ta coù CDF vaỡ PDF cỏỳp hai nhổ sau: {} 21 21 2 12 2 121 2 22 1 121 2 12 xx)t,t,x,x(F)t,t,x,x(fx)t(,x)t(p)t,t,x,x(F== xxCDF PDF Hỗnh 2. 16 CDF ... hai:)(m)t,t(m 22 12 =. Cho , luùc õoù coù thóứ coi hai õaỷi lổồỹng ngỏựu nhión )t(1 vaỡ )t( 2 õọỹc lỏỷp vồùi nhau vaỡ PDF hai chióửu cuớa noù bũng: )x(f)x(f)t,x(f)t,x(f)t,x,t,x(f 21 1 122 111 122 1 12 ==...