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AP EAMCET202422 May 2024Morning ShiftMathematicsSequences and SeriesActual

2+3+5+6+8+9+ . .+2 n terms =

Options

  1. A3 n^2+2 n
  2. B4 n^2+2 n
  3. C4 n^2
  4. D5 n^2+2 n

Correct answer

A. 3 n^2+2 n

Step-by-step solution

aligned & Required sum =1+2+3+4 . upto (3 n+1) terms & -(4+7+10 . n terms )-1 & = (3 n+1)(3 n+2) 2 - n 2 [8+(n-1) 3]-1 & = 9 n^2+9 n+2-3 n^2-5 n-2 2 =3 n^2+2 n aligned

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