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Prove by induction

((x/y)^n+1)<((x/y)^n) n≥1 and 0

Prove by induction ((x/y)^n+1)<((x/y)^n) n≥1 and 0-example-1
User Maths Noob
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((x/y)^(n+1)) > ((x/y)^n) for all n ≥ 1 and x > y > 0.

To prove this statement by induction, we will use the principle of mathematical induction.

Base case: When n = 1, we have:

((x/y)^(1+1)) = ((x/y)^2) = (x^2)/(y^2)

((x/y)^1) = (x/y)

Since x > y > 0, we have x/y > 1. Therefore, (x^2)/(y^2) > (x/y), which means that the base case is true.

Inductive step: Assume that ((x/y)^(k+1)) > ((x/y)^k) for some arbitrary positive integer k. We want to prove that this implies that ((x/y)^(k+2)) > ((x/y)^(k+1)).

Starting with ((x/y)^(k+2)), we can write:

((x/y)^(k+2)) = ((x/y)^(k+1)) * ((x/y)^1)

Using the induction hypothesis, we know that ((x/y)^(k+1)) > ((x/y)^k), and we also know that x/y > 1. Therefore, we have:

((x/y)^(k+2)) > ((x/y)^k) * (x/y)

Simplifying this expression, we get:

((x/y)^(k+2)) > ((x/y)^k) * (x/y)

((x/y)^(k+2)) > ((x^k)/(y^k)) * (x/y)

((x/y)^(k+2)) > ((x^(k+1))/(y^(k+1)))

Therefore, we have shown that ((x/y)^(k+2)) > ((x/y)^(k+1)) for all positive integers k, which completes the inductive step.

By the principle of mathematical induction, we have proven that ((x/y)^(n+1)) > ((x/y)^n) for all n ≥ 1 and x > y > 0.

User Doug Denniston
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