习题2.4

import numpy as np
import matplotlib.pyplot as plt

# 定义x的范围
x = np.linspace(-10, 10, 400)

# 创建一个2行3列的子图网格
fig, axs = plt.subplots(2, 3, figsize=(12, 8))

# 遍历k值，并在对应的子图中绘制函数图像
k_values = [1, 2, 3, 4, 5, 6]
x_limits=[(-5,5),(-10,10),(-15,15),(-20,20),(-25,25),(-30,30)]
for i, k in enumerate(k_values):
    row = i // 3  # 计算行索引
    col = i % 3  # 计算列索引
    y = k * x ** 2 + 2 * k  # 计算y值
    axs[row, col].plot(x, y, label=f'k={k}')
    axs[row, col].set_title(f'y = {k}x^2 + 2{k}')
    axs[row, col].legend()
    axs[row,col].set_xlim(x_limits[i])

# 调整子图之间的间距和布局
plt.tight_layout()

# 显示图形
plt.show()