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Originally posted by gnome-kde at 2005-4-6 20:30:
% f" N! F4 _7 z. x7 f# `1 F9 }这样算混淆了微分和导数的概念。
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9 d# Z; M' ^8 a; Fd(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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8 s5 P( V2 M; b" h% N# g+ W0 N1 {这样算混淆了微分和导数的概念。
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0 ], _% d0 P: h$ j2 od(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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! k) ]0 [0 n6 K: N" H: S0 m; T2 GAh, you made a mistake: it should be:
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# j# T, ` K, I2 [d(f(x)g(x))/dx = f(x) d(g(x))/dx + g(x) d(f(x))/dx 4 W5 Z/ t$ H) {% _3 d/ B
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- l6 c' s, C$ }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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0 G3 j$ q4 c5 ~. Z5 b$ nfor h(x)=(a+bx)*C(x)/x, you are right, But, no x there, it is:
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h(x)=(a+bx)*C(x) |
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