118 reputation
2
bio website andresbotero.co
location Colombia
age 28
visits member for 2 years, 9 months
seen Dec 24 '12 at 2:38

Sep
30
awarded  Scholar
Sep
30
accepted Trigonometric identity proof
Sep
30
comment Trigonometric identity proof
Nice, keeping-it simple approach (plus the addition in the edit). I will choose Srivatsan Narayanan answer mostly because he took off from there I left. In any case, thank you very much! PS: I’m reading your other answer, and some linked in that question.
Sep
30
comment Trigonometric identity proof
Yes, but I didn’t think of that approach. How would have been? cos(A + 0)? (Trying it right now)
Sep
30
comment Trigonometric identity proof
Excellent question! No, I did not have the half-angle formulas. Many answers already, but I didn’t mention anything of half-angle because I didn’t even know about them until now.
Sep
30
comment Trigonometric identity proof
Yes, I solved it using the 1 - 2sin^2x variant, but I would really appreciate if you could please explain the above inquiry before checking this topic. Oh, by the way: thank you!
Sep
30
awarded  Student
Sep
30
comment Trigonometric identity proof
@Srivatsan I mean, why the double angle formulas? Simply because they could work? Sorry, perhaps I’m overcomplicating, but I’m trying to understand the background of that decision.
Sep
30
comment Trigonometric identity proof
Wait a minute, why 2x now? I mean, why the double angle now? How did you come to the conclusion that you should use those formulas in order to solve the problem? I mean, besides “experience”.
Sep
30
asked Trigonometric identity proof