Class 11

Math

Algebra

Sequences and Series

If $a_{1},a_{2},...a_{n}$ be an A.P. of +ive terms, then $k=1∑n a_{k}≥na_{1}+(n−1)da_{1} $ where d is common difference of A.P. If you think this is true write $1$ otherwise write $0$ ?

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or $S_{n}≥na_{1}[a_{1}+(n−1)d] =na_{1}+(n−1)da_{1} $

Thus answer is $1$.