Question

Yi z

想請問A選項為什麼axb不是log5+log2
C選項看起來跟A選項很像
我好像分辨不出來

已知a=log5,b=log2,下列何者正確?
5
(A)axblog 5+log2 (B) a÷b=
log 5
=-
a+b=1 (D)a-b=
2
log 2
,
a=log 5 b=log 2
(A) axb=(log5)x(log2)
a log 5
(B)
=
b
log2
= log₂ 5
(C) a+b=log5+log 2 = log(5×2) = log 10=1
(D) a − b = log 5-log 2 = log
(2)
5

Answer 1

qn

加變乘、乘變加
兩個不要搞反就好
log(xy) = logx + logy
log(x+y) ≠ logx · logy

然後 logx · logy ≠ logx + logy
換個符號看看 mn ≠ m + n

Yi z

太好了！謝謝🙏🏻🙏🏻