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Question
Convert the following products into factorials:
3 · 6 · 9 · 12 · 15 · 18
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Solution
\[\ 3 \times 6 \times 9 \times 12 \times 15 \times 18 = \left( 3 \times 1 \right) \times \left( 3 \times 2 \right) \times \left( 3 \times 3 \right) \times \left( 3 \times 4 \right) \times \left( 3 \times 5 \right) \times \left( 3 \times 6 \right)\]
\[ = 3^6 \left( 1 \times 2 \times 3 \times 4 \times 5 \times 6 \right)\]
\[ = 3^6 \left( 6! \right)\]
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