定积分定义动画演示

402

Clear[f, x, a, b];
/ G7 S# X. H- e4 `; Tf[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   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;
- n5 a/ c, p. l# `3 J+ }  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
( r; T. J1 X& B# ^! ^) Z    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
- o7 f" Y4 q: @: n  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？

( s6 n) c9 k# N, F5 M8 g' h' b) cf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
' }# ~4 ^3 I. ~$ h! x2 ~, C For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
' |9 G4 Z. ?7 v7 O4 ~* w  t1 = Append[t1,
7 o1 M. {0 h  Q# _5 C2 u( O    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
$ ?6 e0 n6 Z- n1 a1 \: r9 L& |  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
" g( [6 D8 Y! p8 e% D- |# A Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
0 b0 D" {$ |8 ]  PlotLabel -> n "intervals"]]
. x; H# S8 A0 g9 J
9 G6 j8 \; ~- G( R

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meiya

好牛，厉害

z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看
$ S4 u; H0 I" Z. x6 A) e

宏心

牛。牛牛。

402

已经解决。谢谢小木虫的大虾。
5 o/ X; Q1 O% j7 n# N) Y# Uf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
- O+ ^& O2 y; D* Q  V2 }9 uAnimate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
& N. l  s# h9 |" z( x6 b  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
; r6 U% n* v) t/ q" K0 |  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
; {; ^1 J1 x8 r9 \ Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
( ]& v4 x' E( n4 Q  X5 G AnimationRunning -> False]
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变动的永恒

太高端，不懂，帮顶