Jika xy = 40 dan log x-log y = 1, maka x-y = ...
A. 18 B. 20 C. 22 D. 24 E. 25
Jawaban:
Log (x/y) = 1 -> log (x/y) = log 10 -> x/y = 10 -> x = 10y -> x = 10.2 = 20.
X.Y = 40 -> 10y. y = 40 -> y2 = 4 -> y = 2.
X-Y = 20 - 2 = 18 (A). ***
Jika xy = 40 dan log x-log y = 1, maka x-y = ...
A. 18 B. 20 C. 22 D. 24 E. 25
Jawaban:
Log (x/y) = 1 -> log (x/y) = log 10 -> x/y = 10 -> x = 10y -> x = 10.2 = 20.
X.Y = 40 -> 10y. y = 40 -> y2 = 4 -> y = 2.
X-Y = 20 - 2 = 18 (A). ***
Editor: Medina Sylvia Riyanto
Sumber: YouTube