Series Summation: Does the Ratio Test Determine Convergence or Divergence?

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I have this HW problem: Suppose Un and Vn are sequences of positve numbers such that the ratio of Un+1/Un will always we less than Vn+1/Vn. Show that 1) If Vn converges Un converged and 2) If Un diverges, Vn diverges.

I did the first part by showing that for any n, the ration of Un/Vn is decreasing and if lim of the ratio=M then Un=MVn.

Stuck on the second part.
 
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Thread 'Finding the nth roots of a complex number'

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