Multiply [[1,2],[3,4]] + [[1,1],[1,1]]: animated lesson

1. 1. The problem
   Worked example

   A + B: A = [[1, 2], [3, 4]]
2. 2. Step by step
   1. $$A = \begin{bmatrix}1 & 2 \\ 3 & 4\end{bmatrix}\ (2×2)$$
      Read matrix A
   2. $$B = \begin{bmatrix}1 & 1 \\ 1 & 1\end{bmatrix}\ (2×2)$$
      Read matrix B
   3. $$c_{11} = 1 + (1) = 2$$
      Add matching entries
   4. $$\begin{bmatrix}2 & 3 \\ 4 & 5\end{bmatrix}$$
      Result
3. 3. The answer
   $$\begin{bmatrix}2 & 3 \\ 4 & 5\end{bmatrix}$$

   [[2, 3], [4, 5]]

4. 4. Check
   • ✓All arithmetic is exact (fractions, no rounding).

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