F.4 maths
2014-05-09 10:57 pm
Without using a calculator, find the values of the following expressions.
1. log√8 + log√1252. log√0.1 +log 0.013. 1/2 log135 + log50 –3/2log15
回答 (3)
2014-05-09 11:39 pm
✔ 最佳答案
1. log√8 + log√125
= 0.5 (log 8 + log 125)
= 0.5 log 1000
= 1.5
2. log√0.1 + log 0.01
= 0.5 log 0.1 + log 0.01
= -0.5 - 2
= -2.5
3. (1/2) log 135 + log 50 – (3/2) log 15
= (1/2) (log 135 + log 2500 - log 3375)
= (1/2) log(135*2500/3375)
= (1/2) log 100
= 1
2014-05-09 17:37:33 補充：
2. log√0.1 - log 0.01
= 0.5 log 0.1 - log 0.01
= -0.5 + 2
= 1.5
2014-05-10 12:20 am
2.
log √0.1 - log 0.01
= (1/2) log 10⁻¹ - log 10⁻²
= (1/2) (-1) log 10 - (-2) log 10
= -(1/2) + 2
= 3/2
= 1.5
log √0.1 - log 0.01
= (1/2) log 10⁻¹ - log 10⁻²
= (1/2) (-1) log 10 - (-2) log 10
= -(1/2) + 2
= 3/2
= 1.5
2014-05-09 11:53 pm
1. log√8 + log√125
=log√8x125
=log√1000
=log10^1.5
= 1.52. log√0.1 +log 0.01
=log10^-1/2+log10^-2
=log10^-1/2x10^-2
=log10^-2.5
=-2.53. 1/2 log135 + log50 –3/2log15=log135^0.5 + log50+log15^-1,5
=log(135^0.5x50x15^-1,5)
=log(10)
=1
=log√8x125
=log√1000
=log10^1.5
= 1.52. log√0.1 +log 0.01
=log10^-1/2+log10^-2
=log10^-1/2x10^-2
=log10^-2.5
=-2.53. 1/2 log135 + log50 –3/2log15=log135^0.5 + log50+log15^-1,5
=log(135^0.5x50x15^-1,5)
=log(10)
=1
收錄日期: 2021-04-13 22:13:27
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140509000051KK00056