Proving inequality with mathematical induction

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I am having trouble proving these. I cannot figure out how to get to the conclusion. Here is my attempt. The stuff in red is just side work and is not part of the proof. I always get stuck on these types of problems, can someone offer some tips on how to approach these kind of problems in general? Should I start with the right hand side or the left hand side of the inequality?

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The goal is to show that 5k+1+9<6k+1. A good place to start is to note that 6k+1 = 6*6k > 6*(5k+9) by the inductive hypothesis like your sidework does. Then it suffices to show that
5k+1+9 < 6(5k+9)
 
I think I got it. So,
5k+1 +9 < 6(5k+9)
5*5k + 9 < 6*5k + 54
5*5k < 6 * 5k since 5 < 6
5*5k + 9 < 6 * 5k + 54 since 9<54

Does this look right?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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