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Multiply two matrices

Suppose ${\bf A}$ is the following matrix:

${\bf A} = \begin{bmatrix} 0.1 & 0.2 & 0.3\\ 0.2 & 0.8 & 0.1\\ 0.4 & 0.1 & 0.8\\\end{bmatrix}$

In code this is:

1	A = [0.1 0.2 0.3; 0.2 0.8 0.1; 0.4 0.1 0.8];

1	A = {{0.1, 0.2, 0.3}, {0.2, 0.8, 0.1}, {0.4, 0.1, 0.8}};

import numpy as np

A = np.array([[0.1, 0.2, 0.3], [0.2, 0.8, 0.1], [0.4, 0.1, 0.8]])

A = matrix(c(0.1, 0.2, 0.3, 0.2, 0.8, 0.1, 0.4, 0.1, 0.8), nrow = 3, ncol = 3, byrow = TRUE)

from sympy import *

A = Matrix([[0.1, 0.2, 0.3], [0.2, 0.8, 0.1], [0.4, 0.1, 0.8]])

What is the matrix ${\bf B} = {\bf A}{\bf A}^T$?

${\bf B} =$

Note: this is an example of a question generator with randomized parameters, which is used to generate a fixed question variant for an exam. Students receive instant feedback and have retry attempts for partial credit.

${\bf B} =$ [0.14 0.21 0.30; 0.21 0.69 0.24; 0.30 0.24 0.81]

${\bf B} =$ [[0.14, 0.21, 0.30], [0.21, 0.69, 0.24], [0.30, 0.24, 0.81]]

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Question

QID:

demo/annotated/mathMatrixMultT

Title:

Multiply two matrices

Variant

Started at:

2026-09-19 08:00:48 (CDT)

Duration:

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{
  "B": {
    "_type": "ndarray",
    "_dtype": "float64",
    "_value": [
      [
        0.14,
        0.21000000000000002,
        0.3
      ],
      [
        0.21000000000000002,
        0.6900000000000001,
        0.24000000000000005
      ],
      [
        0.3,
        0.24000000000000005,
        0.8100000000000002
      ]
    ]
  }
}

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