Given n = 3, evaluate (frac{1}{(n-1)!} – frac{1}{(n+1)!})
-
A.
(12) -
B.
(2frac{1}{2}) -
C.
(2) -
D.
(frac{11}{24})
Correct Answer: Option D
Explanation
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})