香港寵物小精靈村落 論壇

標題: 中三指數定律 [打印本頁]

作者: 雪散霞花    時間: 5/10/2008 06:10 PM
標題: 中三指數定律
化簡下列數式~並以正指數表示答案~而a=/=0~

(2a^-2+a^-2)^3

我既答案係            27
        8a^6

但係正確答案係 27
        a^6
作者: sapphire    時間: 5/10/2008 06:40 PM
[2a^(-2) + a^(-2)]^3
= [(2 + 1)a^(-2)]^3
= [3a^(-2)]^3
= 27a^(-6)
= 27 / a^6

The answer is correct.
It seems that you miscalculate and give out an extra 1/2. Then after the power of 3, it gives out 1/8. Try to find the error by checking each step.

[ 本帖最後由 sapphire 於 5/10/2008 06:44 PM 編輯 ]




歡迎光臨 香港寵物小精靈村落 論壇 (https://proxy.archiver.hkpnve.pokebeacon.com/)Powered by Discuz! X3.2