1.若9^(x+2)=36,則3^x=?
2.若a及b均為正數,則 1/√a^3 ÷ √b/a =
A. √b/ab
B. √ab/b
C. √ab/ab
D. (√a^3b)/b
F4 maths 指數函數
2013-02-24 11:34 pm
回答 (2)
2013-02-25 12:09 am
✔ 最佳答案
1.若9^(x+2)=36,則3^x=?36=(3^2)^(x+2)=3^(2x+4)=3^(2x)*3^4=81*3^(2x)3^(2x)=36/813^x=√(36/81)=6/9=2/3......ans2.若a及b均為正數,則w=1/√a^3 ÷ √b/a=w=(1/√a^3)*(a/√b)=a/(a√a*√b)=1/√(a*b)=√(a*b)/(a*b)......ans=(C)
2013-02-25 12:10 am
1/.3^2(x+2)=36
3^2x(3^4)=36
3^2x=36/81
3^x=4/9
第二條是c
因為通常計到答案是1/root of ab
冇化為有理數
(1/root of ab)(root of ab/root of ab)
3^2x(3^4)=36
3^2x=36/81
3^x=4/9
第二條是c
因為通常計到答案是1/root of ab
冇化為有理數
(1/root of ab)(root of ab/root of ab)
收錄日期: 2021-04-16 15:35:59
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