Jika log 3 = 0,4771 dan log 2 = 0,3010, maka nilai dari log 75 =

log 3 = 0,4771
log 2 = 0,301

log 75
= log (3 × 5²)
= log 3 + 2 log 5
= log 3 + 2 log (10/2)
= log 3 + 2log 10 - 2log 2
= 0,4771 + 2 - 2(0,301)
= 0,4771 + 2 - 0,602
= 1,8751

log 75 = log (25 . 3)
= log 25 + log 3
= log 5² + log 3
= 2 . log 5 + log 3
= 2 . log (10/2) + log 3
= 2 (log 10 - log 2) + log 3
= 2 (1 - 0,3010) + 0,4771
= 2 - 0,6020 + 0,4771
= 1,8751