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प्रश्न
Find S10 if a = 6 and d = 3
उत्तर
a = 6 and d = 3 ......[Given]
Since Sn = `"n"/2[2"a" + ("n" - 1)"d"]`,
S10 = `10/2[2(6) + (10 - 1)(3)]`
= 5[12 + 9(3)]
= 5(12 + 27)
= 5(39)
= 195
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Sn = `"n"/2 [square + ("n" - 1)"d"]` - Formula
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= `27/2 xx square`
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