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प्रश्न
If the sum of first p terms of an A.P. is equal to the sum of the first q terms, then find the sum of the first (p + q) terms.
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उत्तर
Let a and d be the first term and the common difference of the A.P. respectively.
Here,
Thus, the sum of the first (p + q) terms of the A.P. is 0.
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