Для членов арифметической прогрессии с разностью 2 верно равенство (a11 - a6)(a121 - a103)=360

Предыдущий
вопрос Следующий
вопрос

a11 = a1 + 10
a6 = a1 + 5
a121 = a1 + 120
a103 = a1 + 102d

(a11 - a6)(a121 - a103) = 36
(10d)(18d) = 36
180d^2 = 36
d^2 =
d = √2 or d = -√2

Since d is the common difference of an arithmetic progression, it must be a positive integer. Therefore, d = √2 is not valid, and d = √2 can be disregarded.

Therefore, the common difference of the arithmetic progression is d = √2.