Q. 64.0( 4 Votes )
Prove that 91/3 × 91/9 × 91/27 × …..∞ = 3
Answer :
L.H.S=91/3 × 91/9 × 91/27 × …..∞
=9(1/3)+(1/9)+(1/27)+…∞
The series in the exponent is an infinite geometric series
Whose, a
∴Sum of the series in the exponent
∴L.H.S=91/2
=3=R.H.S
Hence, Proved that 91/3 × 91/9 × 91/27 × …..∞ = 3
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