定积分定义动画演示

402

Clear[f, x, a, b];
# j' T" |* k# A/ g# Z+ Cf[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
) j$ y& a% S+ q9 V  r6 X$ h% q* cFor[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;
  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
4 c% p/ e" c. s# |5 \  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]

2 K( T& O) l: Z7 g4 D  n* X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？

5 [% x; j# B! A. r* C* N% i+ @- Pf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
, ^, l+ m% u4 n" Ig = Plot[f[x], {x, a, b}, PlotStyle -> Red,
, s' Q( p, f: Z. K- V  DisplayFunction -> Identity]
. I* o% t) i4 Q3 J3 ~For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
" Y# w& K* ?: x For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
0 M" O. s$ t+ d: \) I# k    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
* j( [8 y" ~9 Z0 {) g2 [  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];
Animate[t1 = {}; t2 = {};
! h! V" g- N3 J For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
. U6 w: U" O2 w9 D/ k  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
6 p( z3 @2 H. m9 G% B2 F5 T Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
+ e5 J3 w" T7 @7 C AnimationRunning -> False]
. m  G9 h) O! \$ F( H$ T) b

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