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anonymous
 5 years ago
Help with trigonometry identities please!
Simplify:
a) cos(180º +x) + cos(180º  x)
b) cos(7pi/126º)cos(36º/5)+sin(7pi/126º)sin(36º/5)
anonymous
 5 years ago
Help with trigonometry identities please! Simplify: a) cos(180º +x) + cos(180º  x) b) cos(7pi/126º)cos(36º/5)+sin(7pi/126º)sin(36º/5)

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amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0cos(a+b)  cos(ab): cos^2(a)  sin^2(a) + cos^2(a) + sin^2(a) 2cos^2(a) 2cos^2(180) ; cos(180) = 1 2(1^2) = 2(1) = 2

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0if anything that would equal 7pi(180)/126pi ... but ive never seen anything written like that before.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0this is the equation:

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0well, its a cos(ab) construct, but i dunno about those digits

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0if you convert the degrees to radians, then I spoose you can have a radian measure without a pi in it.... but its just unnatural :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok..thanks for the help on the first one

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.07pi = 180 degrees, lets substitute that in instead

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0cos(180/126)cos(36/5) + sin(180/126º)sin(36/5)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0then cos(180/126  36/5) is your angle....

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0add the fractions and simplify... right?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0602/105...whats our remainder?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0did u already multiply the fraction by cos? im confused, sorry :S

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0you dont need to do that :) you just need to find the angle of the cos: cos(a  b); find a  b

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0108(5) 36(126)    126(5) 126(5)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0180(5) 36(126)    126(5) 126(5) arghh!!..typoed it lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.03636 cos of  is what I get 630

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.03636  you gotta catch this stuff, cause I dont always ;) 630

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Amistre please help :'(

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0that looked alot better in my head lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0loco..... give me a sec; im on break ;)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im not about to catch anything lol. i am very confused by trig in general..im about to post a question on trig identities...could u maybe help me through those when i post it? u seem like u know what ur doing :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0its a farse, I no nutheeenng!!!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0he does. he know his stuff :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ur a superhero for a reason :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0pfftt!!!.....super hero, now I gotta wear tights, and that aint a pretty picture ;)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0I get an angle of 5.77 degrees when we do all that.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0that is if its even right lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0the cos of that angle = .9949 and thats the best I got fer ya on that one....right or wrong ;)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0r u solving the whole question btw? i just need to simplify..

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0I solved it for the angle; andle = 5 + (77/105) and for the value of the cosine of that angle :=: .9949 how to simplify it is beyond me :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0:'( ok. that's better than no answer at least!

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.0well, 5 and 77/105ths.... but yeah :) ..good luck with it; if anything, get it wrong and move ahead :)
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