 鲜花( 19)  鸡蛋( 0)
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Originally posted by gnome-kde at 2005-4-6 20:30:
; M$ h j) m& q& B这样算混淆了微分和导数的概念。5 H; J C( ]; F: \- x, |4 P
& H2 E" p4 ^, K, B9 O: a* ^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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- o1 @1 P: p3 |* R6 i! a- l这样算混淆了微分和导数的概念。. t7 X1 b8 b t9 ~
! ~5 ^$ H9 ^% K/ sd(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- T, n' a( B$ G; q, r
$ I" [) I6 v9 e6 n; a9 YAh, you made a mistake: it should be:0 X( a/ @6 ~' W4 T6 ~
8 ?' q% j) \# Ad(f(x)g(x))/dx = f(x) d(g(x))/dx + g(x) d(f(x))/dx
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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)/ B: O, w2 ]' j- |+ H
0 g" }9 i' @: t! [' ]. Pfor h(x)=(a+bx)*C(x)/x, you are right, But, no x there, it is:
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- D- c6 Q. a( H" Zh(x)=(a+bx)*C(x) |
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