Question

Find the sum of the first 25 terms of the arithmetic sequence2, 6, 10, 14 ………..​

Answer 1

Answer:

clearly common difference is 4

a= 2

so sum ka formula lagao

You will get 1225

Answer 2

Answer:

The sum of the first 25 terms of the given AP is 1250.

Step-by-step-explanation:

The given arithmetic progression is 2, 6, 10, 14, ....

• a = t₁ = 2
• d = t₂ - t₁ = 6 - 2 = 4

We have to find the sum of the first 25 terms of the AP.

We know that,

Sₙ = ( n / 2 ) * [ 2a + ( n - 1 ) * d ]

⇒ S₂₅ = ( 25 / 2 ) * [ 2 * 2 + ( 25 - 1 ) * 4 ]

⇒ S₂₅ = ( 25 / 2 ) * ( 4 + 24 * 4 )

⇒ S₂₅ = ( 25 / 2 ) * 4 ( 1 + 24 )

⇒ S₂₅ = 25 * 4 ÷ 2 * 25

⇒ S₂₅ = 25 * 2 * 25

⇒ S₂₅ = 50 * 25

⇒ S₂₅ = 1250

∴ The sum of the first 25 terms of the given AP is 1250.