Question

Find the 15th term of the A.P with second term 11 and common difference is 9.

this is the highest mark plz solve this​

Answer 1

Heya!

Here is ur answer...

Given,

Second term of an AP = 11

and, Common difference = 9

Now,

second term(a2)= a+d

a+d = 11

a+9 = 11

a = 11-9

a = 2

Now,

15th term(a15) = a+14d

a15 = 2+14(9)

a15 = 2+126

a15 = 128

Therefore,

15th term = 128

Hope it helps u..

Answer 2

Answer:

128

Step-by-step explanation:

Given: Second term is 11 and common difference is 9.

∴ a₂ = 11

⇒ a + (n - 1) * d = 11

⇒ a + (2 - 1) * 9 = 11

⇒ a + 9 = 11

⇒ a = 2

Now,

15th term:

a₁₅ = a + (15 - 1) * d

    = 2 + 14 * 9

    = 128

Therefore, 15th term of the A.P is 128.

Hope it helps!