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If Tn = 6n + 5, find Sn. |
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Answer» Tn = 6n +5 => a +(n-1)d = 6n +5 => a +(n-1)d = 11 + 6n - 6 => a +(n-1)d = 11+ 6(n-1) Comparing both sides, we get a= 11 d = 6 Sn = n/2 [ a + Tn] = (n/2) ( 11+6n +5) = (n/2) (6n +16) = n(3n + 8) = 3n^2 + 8n HIT THE LIKE BUTTON ✔️👍 |
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