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Trigonometric Half angles and compound angles questions (1 Viewer)

M@ster P

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I need help with these questions

1. sinx + 1 - cosx / sinx - 1 + cosx = 1 + tan(x/2) / 1 - tan(x/2)


2. sinA + sin(90 - A) + 1 / sinA - sin(90 - A) + 1 = cot(A/2)


3. cot (x+y) = cotxcoty - 1/ cotx + coty


4. 2cos(x/2) - 1 - cosx / 2cos(x/2) + 1 + cosx = 1 - cos(x/2) / 1+ cos(x/2)


5. Find tan x in terms of tanA if tanA = cos (A + x) / cos(A - x)


Its alot of questions... but it would be great if you guys could help me
 

shaon0

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M@ster P said:
I need help with these questions

1. sinx + 1 - cosx / sinx - 1 + cosx = 1 + tan(x/2) / 1 - tan(x/2)


2. sinA + sin(90 - A) + 1 / sinA - sin(90 - A) + 1 = cot(A/2)


3. cot (x+y) = cotxcoty - 1/ cotx + coty


4. 2cos(x/2) - 1 - cosx / 2cos(x/2) + 1 + cosx = 1 - cos(x/2) / 1+ cos(x/2)


5. Find tan x in terms of tanA if tanA = cos (A + x) / cos(A - x)


Its alot of questions... but it would be great if you guys could help me
I would help but there is just way too many questions and i just can't be bothered, sorry.
Just wait for someone like 3unitz, lyounamu to help.
 

12o9

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Oh crap. can someone teach me how to resize the images? my bad =/

btw 5 is probably wrong
 
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lyounamu

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shaon0 said:
I would help but there is just way too many questions and i just can't be bothered, sorry.
Just wait for someone like 3unitz, lyounamu to help.
I was sleeping at that time. Lol

For q5, just rearrange it like this:
tan a = (1-tanatanx)(1+tanatanx)
tan a + tan^2(a)tanx = 1-tanatanx
tan a + tan^2(a)tanx + tanatanx - 1
tanx(tan^2(a) + tana) + tana - 1 = 0
tanx(tan^2(a) + tana) = 1-tana
tan x = (1-tana)/(tan^2(a) + tana)
 
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