Question

a b c d e f are in A.P then find the value of a^(2)-b^(2)+c^(2)-d^(2)+e^(2)-f^(2) having common difference D=-1 .​

Answer 1

Answer:

common difference of an arithmetic progression is 3 and find a20 - a15 .If the sum of first n terms of AP is 6n-n^2 find its 25th term.

Step-by-step explanation:

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