Question

6. If log30 3 = x, log30 5 = y, then log30 8
(a) 3 (1 - x - y)
(c) 1 - x - y
(b) x - y + 1
(d) 2 (x - y +1)​

Answer 1

Answer:

3(1 - x - y)

Step-by-step explanation:

log30 3  +  log30  5  =   log30  15    (logz ab = logz a + loz  b)

log30  15 = x + y

log30 30  +  log30  (1/2)  =  x + y         (30*(1/2))  =  15

1  + log30  (1/2)  =  x + y

-log30  (1/2)  =  1 - x - y

log30 2 = 1 - x - y

Multiplying by 3 on both sides

3(log30 2) = 3(1 - x - y)

log30 2³ =  3(1 - x - y)

log30 8  = 3(1 - x - y)