Question

If the n^th term of an A.P. is 5n – 6, then its common difference is ______.

विकल्प

• –6

• 5n

• 5

• 6

Answer 1

If the n^th term of an A.P. is 5n – 6, then its common difference is 5.

Explanation:

n^th term of A.P. = 5n – 6

a_n = 5n – 6

⇒ n = 1,

a₁ = 5(1) – 6

= 5 – 6

= (–1)

⇒ n = 2,

a₂ = 5(2) – 6

= 10 – 6

= 4

d = a₂ – a₁

= 4 – (–1)

= 4 + 1

= 5