Question

Jika ³log5=a dan ²log3=b maka nilai dr 18log45 adalah...
a.b(a+2)/1+2b
b.2a+2b/ab
c.a(1+2b)/2+b
d.ab/b(a+2)
e.a+b/2b


ket. 18nya itu kecil diatas dkt log.
mohon cara nya yg runtut . trims

Answer 1

³log 5 = a
²log 3 = b
¹⁸log 45 = ³log 45 / ³log 18
= (³log 9 x 5) / (³log 9 x 2)
= (³log 3² + ³log 5) / (³log 3² + ³log 2)
= (2 + a) / (2 + 1/b)
= (2b + ab) / (2b + 1)

Answer 2

³log5=a
²log3=b 
2log5=ab

18log45 ??
log 45
log 18
=2log 5 x 2 log 3 x 2log 3 (45)
2 log 3 x 2log 3 x 2log 2   (18)
=ab+b+b
 b+b+1
=ab+2b
 2b+1

jadi A
:)