Math, asked by Anonymous, 9 months ago

Joker and jaggu.... The sum of the third and the seventh terms of an AP is 6 and their product is 8. Find the sum of first sixteen terms of the AP.​....Please don't answer ​

Answers

Answered by Anonymous
12

Answer:

Let a and d be the first term and common difference of A.P.

nth term of A.P., an = a + (n – 1) d

∴  a3 = a + (3 – 1) d = a + 2d

a7 = a + (7 – 1) d = a + 6d

Given, a3 + a7 = 6

∴ (a + 2d) + (a + 6d) = 6

⇒ 2a + 8d = 6

⇒ a + 4d = 3     ...(1)

Given, a3 × a7 = 8

∴ (a + 2d) + (a + 6d) = 8

⇒ (3 – 4d + 2d) (3 – 4d + 6d) = 8             [ Using (1) ]

⇒ (3 – 2d) (3 + 2d) = 8

⇒ 9 – 4d2 = 8

⇒ 4d2 = 1

a = 3 – 4d  = 3 – 2 = 1

When a = 1 and  

Thus, the sum of first 16 terms of the A.P. is 76 or 20.

#Capricorn Answers

Answered by Anonymous
4
。☆✼★━━━━━━━━━━━━━━━★✼☆。

\huge\mathfrak{Answer\:♡}

\mathcal{76\:or\:20}

\huge{\ddot{\smile}}

。☆✼★━━━━━━━━━━━━━━━★✼☆。
Similar questions