Q43 of 74 Page 9

Evaluate .


= (2 + 3) + (2 + 32) + (2 + 33) + ….. + (2 + 311).

          = (2 + 2 + ………….. 11 times) + 3 + 32 + 33 + ….. + 311.

a = 3, r = 32/3 = 3 > 1

Sn = = =

Substituting n = 11

S11 =
Therefore the required sum is 22 + .

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