WAEC - Further Mathematics (2016 - No. 14)
Given n = 3, evaluate \(\frac{1}{(n-1)!} - \frac{1}{(n+1)!}\)
\(12\)
\(2\frac{1}{2}\)
\(2\)
\(\frac{11}{24}\)
คำอธิบาย
n = 3, \(\frac{1}{(n-1)!} - \frac{1}{(n+1)!} = \frac{1}{(3-1)!} - \frac{1}{(3+1)!}\)
= \(\frac{1}{2} - \frac{1}{24} = \frac{12 -1}{24}\)
= \(\frac{11}{24}\)