If the sum of n terms of an AP is (pn+qn²),where p and q are constants , find the common difference
Plzz Anwer it ASAP ...
I ll mark bst ans.as brainliest
Answers
Answered by
9
we have,
sum of n terms = pn+qn^2
sum of first term = p×1 + q×1^2
= p + q = first term
sum of first two terms = p×2 + q×2^2
= 2p + 4q
now,
second term = sum of the first two terms - first term
= 2p + 4q - p - q
= p + 3q
we know that common difference = second term - first term
= p + 3q - p - q
= 2q
hence the common difference of the AP is 2q
sum of n terms = pn+qn^2
sum of first term = p×1 + q×1^2
= p + q = first term
sum of first two terms = p×2 + q×2^2
= 2p + 4q
now,
second term = sum of the first two terms - first term
= 2p + 4q - p - q
= p + 3q
we know that common difference = second term - first term
= p + 3q - p - q
= 2q
hence the common difference of the AP is 2q
Similar questions