計算下列各式:
1)5^0+5^-1=?
2)2^0+3^-1+4^-2=?
3)(-7/2)^0+(-2/3)^-1+2^-2=?
4)(3^4-3^-3)÷3^-2=?
5)化簡(-2ab^-1)^-2/4a^2b^2，並以正指數表示答案
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數學5條~~超難!急要ans
2007-09-24 3:00 am
回答 (4)
2007-09-24 3:25 am
✔ 最佳答案
(1)5^0 + 5^-1
=1 + 1/5
= 1 1/5
(2)
2^0 + 3^-1 + 4^-2
=1 + 1/3 + 1/16
=1 + 16/48 + 3/48
=1+ 19/48
=1 19/48
(3)
(-7/2)^0 + (-2/3)^-1 + 2^-2
=1 + -(3/2) + 1/2
=2/2 + -3/2 + 1/2
=(2-3+1)/2
=0/2
=0
(4)
(3^4 -3^-3) / 3^-2
=3^4 - 3^-3 / 3^-2
=81 - 27^-1 / 9^-1
=81 - 9/27
=81 - 1/3
=80 2/3
(5)
(-2ab^-1)^-2/4a^2b^2
=((-4^-1)(a^-2)(b^2))/4a^2b^2
=(b^2-2)/-4+4 a^2+2
=1/0a^4
=1
參考: Mathematician - Charles Lolingfung
2007-10-04 8:06 am
This is my answer!
2007-09-24 3:23 am
1) 5^0+5^-1
=1+1/5=6/5
2) 2^0+3^-1+4^-2
=1+3+1/16
=64/16
3) (-7/2)^0+(-2/3)^-1+2^-2
=1-3/2+1/4
=-1/4
4) (3^4-3^-3)÷3^-2=?
=3^6-3^-1
=729-1/3
=2186/3
5不會
2007-09-23 19:25:02 補充：
2) 2^0+3^-1+4^-2=1+1/3+1/16=67/48
=1+1/5=6/5
2) 2^0+3^-1+4^-2
=1+3+1/16
=64/16
3) (-7/2)^0+(-2/3)^-1+2^-2
=1-3/2+1/4
=-1/4
4) (3^4-3^-3)÷3^-2=?
=3^6-3^-1
=729-1/3
=2186/3
5不會
2007-09-23 19:25:02 補充：
2) 2^0+3^-1+4^-2=1+1/3+1/16=67/48
參考: me
2007-09-24 3:22 am
1) 1.2
2) 67/48
3)-1/4
4)2186/3
2) 67/48
3)-1/4
4)2186/3
收錄日期: 2021-04-18 23:30:04
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https://hk.answers.yahoo.com/question/index?qid=20070923000051KK04276