(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the formula

Σ[n, i =1](2i - 1) = 1+3+5+...+(2n-1)

2. Relevant equations

3. The attempt at a solution

When I look at the back of the book , I got this solution which is

1, Sigma(2i - 1) = 1+3+5+...+(2n-1)

2, = 1+2+3+...+2n-2(1+..+n)

3, = ((2n)(2n+1)) /2 - n(n+1)

4, n^2

What i don't get is what happened from step 1 to 2 and 2 to 3?

It seems that there are hidden steps there that were not written down and therefore and I am really confused about this solution.

Thank you guys very much.

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# Homework Help: Confused about this answer, michael spivak's calculus

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