 鲜花( 19)  鸡蛋( 0)
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Originally posted by gnome-kde at 2005-4-6 20:30:
$ J% Z( \; b- w0 `; e6 \1 t9 F1 m这样算混淆了微分和导数的概念。; Z/ W) ?, p+ ? F" W( p. Y
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d(f(x))/dx = f'(x), d(f(x)g(x))/dx = f'(x) d(g(x))/dx + g'(x) d(f(x))/dx 这是基本的微分四则运算
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If h(x)=(a+bx)*C(x)/x, then d(h(x))/dx = d{(a+bx)*C(x)/x}/dx = h ...
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6 H7 Q: _8 `4 _& b8 j/ B. I& N这样算混淆了微分和导数的概念。
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d(f(x))/dx = f'(x), d(f(x)g(x))/dx = f'(x) d(g(x))/dx + g'(x) d(f(x))/dx 这是基本的微分四则运算
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Ah, you made a mistake: it should be:$ C9 N% t% C$ P6 \5 O5 X5 I1 @
4 I* j1 _/ k) y1 f3 rd(f(x)g(x))/dx = f(x) d(g(x))/dx + g(x) d(f(x))/dx * y- J- i: [- J& M9 v9 y C0 `
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If h(x)=(a+bx)*C(x)/x, then d(h(x))/dx = d{(a+bx)*C(x)/x}/dx = h'(x) = [xb*c(x)+x(a+bx)*c'(x)-(a+bx)*c(x)]/x2 (应该对吧, 我也没验算)
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O6 z1 t' Y6 M5 kfor h(x)=(a+bx)*C(x)/x, you are right, But, no x there, it is:& K5 ]0 p L- ?! e- N
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h(x)=(a+bx)*C(x) |
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