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Question: Answered & Verified by Expert
If 210+29·31+28·32+……+2·39+310=S-211, then S is equal to
MathematicsSequences and SeriesJEE MainJEE Main 2020 (05 Sep Shift 1)
Options:
  • A 311-212
  • B 311
  • C 3112+210
  • D 2.311
Solution:
1140 Upvotes Verified Answer
The correct answer is: 311

S'=210+29·3+28·32+…….+2·39+310

S'=2101+32+322+…….+329+3210

G.P. →a=1,r=32,n=11

S'=210·3211-132-1=211311211-1

=311-211

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