Let x=3+4+3+4+3+…∞1111
So, x=3+4+x11=3+x4x+11
⇒(x−3)=(4x+1)x
⇒(4x+1)(x−3)=x
⇒4x2−12x+x−3=x
⇒4x2−12x−3=0
x=2×412±(12)2+12×4=812±12(16)
=812±4×23=23±23
x=23±3=1.5±3.
But only positive value is accepted
So, x=1.5+3
JEE Main 2021 — Mathematics Algebra
The value of 3+4+3+4+3+…∞1111 is equal to
Held on 18 Mar 2021 · Verified 6 Jul 2026.
1.5+3
2+3
3+23
4+3
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