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

I dont know how other people learned trig, but in my book, the first 2 chapters have nothing to do with angles, but are mostly circles and trig functions of real numbers. Does this make sense to anyone? I am in the next chapter already and I know there are other, easier ways of calculating trig, but in these chapters, I cant do that. I know how to show sin and cos are odd and even with a random number and a calculator, but I have to show it the way presented below. Ive googled and my book only shows the properties with answers, no worked probs. Can anyone explain to me if I am doing this right or what I am doing wrong? thanks!

a few examples

1. f(x)= x^{2}sin x

2. f(x)= x^{3}+ cos x

3. f(x)= xsin^{3}x

4. f(x)= cos(sin x)

2. Relevant equations

even odd properties that have all trig functions odd except cos and sec

3. The attempt at a solution

1. f(-x)= (-x)^{2}sin (-x) = x^{2}sin -x = -f(x)= odd.

the answer says -x^{2}sin x = -f(x) = odd. why am i wrong?

2. f(-x)= (-x)^{3}+ cos(-x) = -x^{3}+ cos x = neither

3. (-x)sin^{3}(-x)

frankly i have no clue how to do that one.

4. cos(sin(-x)) would be cos (-x) = x = f(x) = even?????

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# Homework Help: Even odd trig functions

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