Question

Jika (ax²+4) (x-b) = (m+1) x²+2x-8, maka nilai m adalah...
Pake cara y...

Answer 1

(ax +4)(x-b) = (m+1)x² + 2x - 8
ax² - ab x + 4x - 4b = (m+1) x² + 2x - 8
ax² + (4-ab)x +(-4b) = (m+1) x² + 2x - 8
..
koefisien kiri = koefisien kanan
a = m+1   ......(1) 
4 - ab = 2.......(2)
-4b = -8..........(3)
..
-4b = -8
b = -8 /-4
b = 2 ,
 .
b = 2 sub ke (2)
4 - ab = -2
4 - a(2) = - 2
-2a = -2 - 4
-2a = - 6
a = - 6/-2
a = 3
.
a = 3 sub ke 1
a = m+1
m = a-1
m = 3 -1
m = 2