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;
! p  S& j7 ?' I7 A( w/ Lg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
* q& s/ Y: Y: z7 R/ }- r6 E   DisplayFunction -> Identity];
& D8 z# R. D5 l& U6 e' P% tFor[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
. e* W0 x* o; V7 M- j$ H For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
3 V$ Z/ o" K! b, S) L6 R& r4 U  tt1 = Append[tt1,
3 H( s6 W6 f" `% J    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
2 z# W0 Q& X" T8 ^) g    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
% u( Y& t' V+ Y, W Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]

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;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
. a9 J; |5 `- ~  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
  D# u' o0 a9 z/ ]  V. \  Q8 Y2 [* X    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
; V: T6 t1 `, o3 Q: x/ T  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。
f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
4 H, ?8 N: Y! W# s+ jAnimate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
* q$ O, m' o0 C- B$ _, O4 y  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
: p2 t+ M1 j: L" a+ I6 P% j2 }  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
1 [5 d" g- e/ @# j Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
/ @/ Z% s3 @, E! q/ j AnimationRunning -> False]
6 r9 w) D1 y4 A1 \

宏心

牛。牛牛。

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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