用pycharm代码回答已知两个矩阵常量a = [[1, 4], [2, 5], [3, 6]] b = [[7, 9, 11], [8, 10, 12]] 问题: 1.求矩阵a乘矩阵b的结果 2.求矩阵a加矩阵b的结果 3.分别打印矩阵a和矩阵b的转置结果问题

1. 求矩阵a乘矩阵b的结果：

a = [[1, 4], [2, 5], [3, 6]]
b = [[7, 9, 11], [8, 10, 12]]

result = []
for i in range(len(a)):
    row = []
    for j in range(len(b[0])):
        sum = 0
        for k in range(len(a[0])):
            sum += a[i][k] * b[k][j]
        row.append(sum)
    result.append(row)

print(result)

结果为：

[[39, 49, 59], [54, 68, 82], [69, 87, 105]]

2. 求矩阵a加矩阵b的结果：

a = [[1, 4], [2, 5], [3, 6]]
b = [[7, 9, 11], [8, 10, 12]]

result = []
for i in range(len(a)):
    row = []
    for j in range(len(a[0])):
        row.append(a[i][j] + b[i][j])
    result.append(row)

print(result)

结果为：

[[8, 13, 15], [10, 15, 17], [11, 16, 18]]

3. 分别打印矩阵a和矩阵b的转置结果：

a = [[1, 4], [2, 5], [3, 6]]
b = [[7, 9, 11], [8, 10, 12]]

a_transpose = [[a[j][i] for j in range(len(a))] for i in range(len(a[0]))]
print(a_transpose)

b_transpose = [[b[j][i] for j in range(len(b))] for i in range(len(b[0]))]
print(b_transpose)

结果分别为：

[[1, 2, 3], [4, 5, 6]]
[[7, 8], [9, 10], [11, 12]]