Find the limit of the sequence whose terms are given by an=(e^(2n)+6n)^(1/n)
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this limit is for the form ∞^0
thus lim n-> ∞ e^(2n)+6n)^(1/n) = e^ ( lim n->∞ ln[(e^(2n) + 6n)]/n ) where ln is natural logarithm
now numerator and denominator there tends to ∞
hence by L'hospital rule
we have e^ ( lim n->∞ ln[(e^(2n) + 6n)]/n ) = e^ (lim n-> ∞ 2( e^(2n) + 3) / (e^(2n) + 6n) )
now divide by e^(2n) in both numerator and denominator,
we have e^ ( lim n-> ∞ 2( 1 + 3/e^(2n) ) / ( 1 + 6n/e^(2n) )
now as n-> ∞, e^(2n) grows to ∞ faster than 3 or 6n
hence lim n-> ∞ 3/e^(2n) or 6n/e^(2n) = 0
=> ans = e^2
thus lim n-> ∞ e^(2n)+6n)^(1/n) = e^ ( lim n->∞ ln[(e^(2n) + 6n)]/n ) where ln is natural logarithm
now numerator and denominator there tends to ∞
hence by L'hospital rule
we have e^ ( lim n->∞ ln[(e^(2n) + 6n)]/n ) = e^ (lim n-> ∞ 2( e^(2n) + 3) / (e^(2n) + 6n) )
now divide by e^(2n) in both numerator and denominator,
we have e^ ( lim n-> ∞ 2( 1 + 3/e^(2n) ) / ( 1 + 6n/e^(2n) )
now as n-> ∞, e^(2n) grows to ∞ faster than 3 or 6n
hence lim n-> ∞ 3/e^(2n) or 6n/e^(2n) = 0
=> ans = e^2
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e².....a_n = e^{ [ ln ( e^2n + 6n ) ] / n}...apply L'H to the exponent