Question

which term of the ap -7;-12;-17;-22.... will be -82 ? is -100 any term of the ap? give reason for your answer

Answer 1

Here is the answer ans and -100 isn’t any term of the AP..which is given below

To check that -100 is a term of AP

An=-100

d=-5

a=-7

Now replace this in AP formula

An= a+(n-1)d

-100=-7+(n-1)-5

Open the bracket

-100=-7-5n+5

-100+7-5=-5n

-98=-5n

98=5n

n=98/5

Which doesn’t give us a whole number ..thus is not a member of this ap