Calculate 2 * [[1,2],[3,4]]: animated lesson

1. 1. The problem
   Worked example

   k × A: 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. $$2A = \begin{bmatrix}2 & 4 \\ 6 & 8\end{bmatrix}$$
      Multiply every entry by k = 2
   3. $$\begin{bmatrix}2 & 4 \\ 6 & 8\end{bmatrix}$$
      Result
3. 3. The answer
   $$\begin{bmatrix}2 & 4 \\ 6 & 8\end{bmatrix}$$

   [[2, 4], [6, 8]]

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

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