Jawabanmu

2014-06-28T10:04:38+07:00
Ma’af Cuma bisa bantu nomor 7 aja., ;)
N0.7
2x
²+ 5x+12=0
a=2, b=5, c=12
misal:  
1. α+β= -b/a= -5/2
2. α.β = c/a = 12/2=6
Kemudian,
1.misal : (x1 + x2 )=(2α+4) + (2β+4)                                 
 = 2α+2β+8
                                  
= 2 (α+β)+8
                                
  = 2 (-5/2)+8 = 3

2. misal : (x1 . x2 )= (2α+4)x(2β+4)                                 
  = 4αβ+ 8α + 8β +16
                                 
 =  4(αβ) + 8(α+β) +16
                                  
 = 4 (6) + 8 (-5/2) + 16 = 20

Rumus menyusun persamaan kuadrat:
X²- (x1 + x2)x + x1.x2 =0
X²- 3 + 20 =0 J
awabannya:  D
   



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