if you only must aplied the sum rule, I mean
If you don`t know how find the derivate of sin(x), is aplied the definition
so I did some steps for this problem and got stuck halfway down, please help
find dy/dx
y=1+x-cos(x)
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ok so I got confused with the Pythagorean trig identities and 1 - cos(x) does NOT equal sin(x)
I guess I need help STARTING the problem