Pre-cal: Simplify using sum and difference identities
- Thread starter calc1
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Have you been studying double-angle formulas? Or could you look up sum-of-angle formulas sine and cosine of (A + B) when A=B?
D
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Please tell us which sum and difference identities that you have referred to in your title of the post.
No. Double-angle identities are in our next section. I have not seen anything about when A=B. This is an online course and the material is scant and a bit disjointed.
So . . .
= cos2b/sin2b = cot2b?
D
Deleted member 4993
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Correct!
D
Deleted member 4993
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Originally Posted by calc1
No. Double-angle identities are in our next section. I have not seen anything about when A=B. This is an online course and the material is scant and a bit disjointed.
So . . .
= cos2b/sin2b = cot2b?
I said correct a little too hastily!
If your problem was;
Simplify:
(cos2b-sin2b)/(2sinbcosb)
and if your answer was
= cos(2b)/sin(2b) = cot(2b)
Then only the response is correct.
Notice the grouping symbols - () - for correctness!
Yes. As any other language, punctuation is often critical for meaning. I forget that I need to be more formal online than on my scratch pad.