Элементы комбинаторики

✔ответ ✔

●: 6. Решите уравнение.

( 4k + 3 )! = 11 * ( 4k + 2 )!

( 4k + 3 )! - 11 * ( 4k + 2 )! = 0

( 4k + 3 ) * ( 4k + 2 )! - 11 * ( 4k + 2 )! = 0

( 4k + 2 )! * ( 4k + 3 - 11 ) = 0

( 4k + 2 )! * ( 4k - 8 ) = 0

( 4k + 2 )! = 0

4k - 8 = 0

k ∈ ∅

k = 2

( 4 * 2 + 3 )! = 11 * ( 4 * 2 + 2 )!

39916800 = 39916800

k = 2