Question

Determine o fatorial de 12! + 9
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10!
Simplifique as expressões:
A. 8!
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10!9!

B. n!
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(n-1)!

C. (n+1)!
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n!

Answer 1

$\frac{12!+9!}{10!}\\ \\\frac{12*11*10*9!+9!}{10*9!}\\\\\frac{9!(12*11*10+1)}{10*9!}\\\\\frac{12*11*10+1}{10}\\\\\frac{1321}{10}\\ \\132,1\\\\\\A.\\\frac{8!}{10!9!}\\ \\\frac{8!}{(10*9*8!).(9*8!)}\\\\\frac{8!}{(8!)^2(10*9^2)}\\\\\frac{1}{(8!)(10*9^2)}\\\\B.\\\frac{n!}{(n-1)!}\\ \\\frac{n(n-1)!}{(n-1)!}\\ \\n\\\\\\C.\\\frac{(n+1)!}{n!}\\ \\\frac{(n+1)n!}{n!}\\ \\n+1$