Question

Ann and June were asked to solve a question - If a3 + a7 = 6 and a3.a7= 8 for a given A.P. then Ann got the answer S16= 76 and June got the answer S16= 20. Who got the correct answer​

Answer 1

Answer:

sorry little bit. difficult......,....

Answer 2

Answer:

Step-by-step explanation

A3+A7=6 and A3.A7=8

A3=a+2d

A7=a+6d solve these we get

A=6-8d/2—-(1)

A3.A7=8

(A+2d)(A+6d)=8. Use (1)

(6-8d/2 +2d)(6-8d/2 +6d)=8

Solving this we get

(6-4d/2)(6+4d/2)=8

Use identity (a+b)(a-b)=a^2-b^2

We can write (6/2)^2 -(4d/2)^2

36-16d^2/4=8 (shift 4 to right side)

36-16d^2=32

16d^2=32-36

16d^2=-4

D^2=1/4.

D=1/2

Use (1) A=6-8d/2

A=6-8/4

A=-1/2

S16=16/2{2.-1/2+(16-1)1/2}

S16=8{-1+15/2}

S16=8.13/2

S16=42

So both of them is wrong padhai likhayi m ladkiya aaj kal dhan hi nahi deti sare din bus instagram snapchat chalati hai