Let A be the sum of the first 20 terms and B be the sum of the first 40 terms of the series
12+2⋅22+32+2⋅42+52+2⋅62+…
If B−2A=100λ, then λ is equal to :
Held on 8 Apr 2018 · Verified 6 Jul 2026.
496
232
248
464
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