Derivative of F(x) = 35 cos [ 2pi/365 (x-220) ] + 60?

I have no idea where to begin...

Question

Derivative of F(x) = 35 cos [ 2pi/365 (x-220) ] + 60?

I have no idea where to begin...

anonymous · Answer

lol.  ffaaaauuu.....

anonymous · Answer

I don't know if this is too easy, but the derivative of cos(x) = -sin(x)

anonymous · Answer

Suppose 
$$
h(k) = a \cos ( b(x-220)) + c\
h'(x) =- a b \sin( b(x-220)) \
$$
What are a, b and c in your problem?

anonymous · Answer

A = 35
B = 2pi/365
C = 220

anonymous · Answer

Replace and you are done

anonymous · Answer

Look at C again.

anonymous · Answer

Oh, that's so simple! Thanks so much!! :)

anonymous · Answer

c? umm is it supposed to be -220?

anonymous · Answer

C=60

anonymous · Answer

it's the constant that goes away with the derivative

anonymous · Answer

really? isn't 60 something different? like D?

anonymous · Answer

220 I did not replace with a constant

anonymous · Answer

No it is not

anonymous · Answer

Like jbell0385 said, isn't 60 a constant and become 0 when you find its derivative?

anonymous · Answer

Yeah, I think that's what eliassaab did.

anonymous · Answer

Your answer should look like
$$
F'(x)=-\frac{14}{73} \pi  \sin
   \left(\frac{2}{365} \pi 
   (x-220)\right)
$$

anonymous · Answer

Yes, it looks like that except i didn't simplify 35*(2pi/365). Maybe i should :)

anonymous · Answer

Yes simplify

anonymous · Answer

Okay :) Thanks you guys!

anonymous · Answer

NP

anonymous · Answer

Solved me a big headache :)