Question

Which of the following are APs? If they form an A.P. find the common difference d and write three more terms. -1/2, -1/2, -1/2, -1/2 ....

Answer 1

`-1/2, -1/2, -1/2, -1/2 ....`

Here,

a₂ - a₁ = `(-1/2) - (-1/2) = 0`

a₃ - a₂ = `(-1/2) - (-1/2) = 0`

a₄ - a₃ = `(-1/2) - (-1/2) = 0`

⇒ a_n+1 - a_n is same every time.

Therefore, d = 0 and the given numbers are in A.P.

Three more terms are

a₅ = `(-1/2) - 0 = -1/2`

a₆ = `(-1/2) - 0 = -1/2`

a₇ = `(-1/2) - 0 = -1/2`