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Homework Statement
Please look over my work and tell me if I did something wrong.
Suppose Bn is a divergent sequence with the limit +∞, and c is a constant.
Prove: lim cBn -> ∞ = +∞ for c > 0
Homework Equations
N/A
The Attempt at a Solution
lim Bn -> ∞ = means that for some value K > 0, Bn > K for all n > N.
If c > 0, multiplying all terms by a constant c > 0 will not change the fact of a limit of +∞.
cK > 0, cBn > cK for all n > N meets the definition of a divergent sequence with a limit of +∞ and thus, if Bn is a divergent sequence with the limit +∞, and c is a positive constant:
lim cBn -> ∞ = +∞
...
With an example (c = 1/2)
lim n -> ∞ = n/2
= lim n -> ∞ (1/2)(n) = +∞