Question

the sum of first three terms of an ap is 5 and the sum of first 5 terms is 3 then sum upto 8 terms is​

Answer 1

Step-by-step explanation:

Let the three numbers in the AP be a-d, a and a+d.

So a-d+a+a+d = 3a = 9 or a = 3.

Now (a-d)^2+a^2+(a+d)^2 = 35, or

a^2–2ad+d^2+a^2+a^2+2ad+d^2 = 35, or

3a^2+2d^2 = 35, or

3x3^2+2d^2 = 35, or

2d^2 = 35–27 = 8, or d = 2.

So the terms are: 1, 3 and 5. The sum is already in the question as 9, Which other sum are you referring to?

Answer 2

Answer:

sum8=9

Step-by-step explanation:

sum3=5

sum5=3

sum8=sum3+sum5

=5+3

=8