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Question
Evaluate: 8! – 6!
Solution
8! – 6!
= 8 × 7 × 6! – 6!
= 6! (8 × 7 − 1)
= 6! (56 − 1)
= 6! × 55
= 6 × 5 × 4 × 3 × 2 × 1 × 55
= 39,600
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