For the AP: -3,-7,-11.... can we find directly a30-a20 without actually finding a30 and a20 ? Give reasons for ur answer. Experts please answer and write the reason too in a sentence form including the steps of the sum.
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https://www.meritnation.com/ask-answer/question/for-the-ap-7-11-can-we-find-directly-a30/arithmetic-progressions/1861511