Question

which term of the AP 2,4,6,8.....is126​

Answer 1

Answer:

The sum of last ten terms of the AP: 8,10,12,...,126 is same as the sum of first ten terms of the AP: 126,124,122,...,8.

Therefore, a=126,d=−2 and n=10.

Now, S

10

= 210[2×126+(10−1)×−2]

⇒S

10=5×[252−18]=1170

Answer 2

Answer:

it's answer will be 63. Use the gernal formula of A.P i.e an=a+(n-1)d you can easily get value of n value of an =126 and value of a=2 and value of d=2 by potting values you get answer as 63