2條f.2升f.3數學(主項變換)!!

👨🏻‍🏫 學術台數學

小key

2011-08-26 8:59 am

回答 (4)

[匿名]

2011-08-27 12:49 am

✔ 最佳答案

1.
x=3/(a-b)
x(a-b)=3
a-b=3/x
b=a-(3/x)

2.
d=(3a+b)^2-(3a-b)^2
=(3a+b+3a-b)(3a+b-3a+b)
=(6a)(2b)
=12ab
b=d/(12a)

Hope I can help you!

參考: me

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用戶27207

2011-08-26 9:02 pm

1. x=3/(a-b) [b]
x(a-b)=3
ax-bx=3
bx=ax-3
b=(ax-3)/x
2. d=(3a+b)²-(3a-b)²
d=[(3a+b)+(3a-b)][(3a+b)-(3a-b)] [b]
d=(6a)(2b)
d=12ab
b=d/(12a)

參考: Hope I can help you! ^_^ (From me)

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[匿名]

2011-08-26 10:35 am

1) x=3/(a-b)
a-b=3/x
b=a-(3/x)

2) d=(3a+b)^2-(3a-b)^2
d=9a^2+6ab+b^2-9a^2+6ab-b^2
d=6ab+6ab
d=12ab
b=d/12a

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ronaldcylam

2011-08-26 9:09 am

1. b= a-3/x
2. b=d/12a

2011-08-26 01:09:56 補充：
sorry 第1係 a-(3/x)

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