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

A question asks me to find the first three non-zero terms of ln(cosx)

2. Relevant equations

3. The attempt at a solution

I wrote cos x as 1+(1-cos x), used the power series of ln function, expanded cosx and simplified, here is my answer: 1/2x^2 - 1/6x^4 + 1/16x^6

Is that right?

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# Series expansion of logarithmic function ln(cosx)

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