定积分定义动画演示

402

Clear[f, x, a, b];
f[x_]： = x^2; a = 0; b = 1.5; m = 0;
/ a6 f4 q, C$ D% Gg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
3 s" r1 \0 M- v6 B7 r, h0 s   DisplayFunction -> Identity];
For[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
4 ]2 V' N, B9 [1 X" [  tt1 = Append[tt1,
  B" w( E9 D6 W2 {2 W4 [" Z    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
- h3 Q) d3 Q; @% M$ ~, J Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
! ]& F  i. }0 A" J+ ~/ c' h  PlotLabel -> m'' intervals'']]
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. }" L9 W6 g( {) [6 I3 p6 N7 v5 J定积分的动画演示，运行没有结果，请各位大虾看看错在哪里？

f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
  m2 |/ V  h9 ?! T$ jg = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
+ `1 ]7 {5 x" K/ A+ _2 [+ |For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
$ ~/ I3 C# \. k/ A For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
( H! |* P* c+ R. m0 Q" f  t1 = Append[t1,
; X! P( \0 u3 t! E+ Q$ W6 G6 \    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
. U% Q: `( i$ a; l: k7 u6 ^8 @  W  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
  PlotLabel -> n "intervals"]]


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变动的永恒

太高端，不懂，帮顶

402

已经解决。谢谢小木虫的大虾。
" J( n! ~& |. ~3 Zf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
& X; `. j& h; x# p; Lg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
' l- _/ M  Z: h6 [: W2 x  ^! j For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
2 z, |" D; ~. z% ^8 V  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]

宏心

牛。牛牛。
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z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看
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meiya

好牛，厉害
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