Question
Show that 216 divides 32!. Also, find the largest value of n for which 32! is divisible by 2n. Or What is the largest power of 2 contained in 32!
Solution
32! = 32 x 31 x 30 x 29 x ......... x 3 x 2 x 1
The product contains 32 factors in all of which 16 are even factors. Each even number is divisible by 2.
∴ 32! is divisible by 216.
Also, the powers of 2 contained in 32!
25 from 32, 21 from 30, 22 from 28, 21 from 26, 23 from 24, 21 from 22, 22 from 20, 21 from 18,
24 from 16, 21 from 14, 22 from 12, 21 from 10, 23 from 8, 21 from 6, 22 from 4 and 21 from 2.
∴ divides 32!
divides 32!
Hence, the largest value of n for which divides 32! is n = 31.