Math, asked by SteveUday49, 1 year ago

CosA-cos3A-cos5A+cos7A/SinA-sin3A+sin5A-sin7A=Tan2A

Answers

Answered by bluelinebus4
6
cos7A + os3A = 2cos5Acos2A 
cos5A + cosA = 2cos3Acos2A 
(cos7A + os3A) - (cos5A + cosA) = 2cos2A(cos5A - cos3A) 
sin7A - sin3A = 2cos5Asin2A 
sin5A - sinA = 2cos3Asin2A 
(sin7A - sin3A) - (sin5A - sinA) = 2sin2A(cos5A - cos3A) 
(cos7A + os3A - cos5A - cosA)/(sin7A - sin3A - sin5A + sinA)
= {2cos2A(cos5A - cos3A)}/{2sin2A(cos5A - cos3A)} 
= cot2A

SteveUday49: prove that Tan2A
SteveUday49: not cot 2 A
SteveUday49: ok thanks for that and I did that problem
Answered by suhaa6
9

cos7A + os3A = 2cos5Acos2A 

cos5A + cosA = 2cos3Acos2A 

(cos7A + os3A) - (cos5A + cosA) = 2cos2A(cos5A - cos3A) 

sin7A - sin3A = 2cos5Asin2A 

sin5A - sinA = 2cos3Asin2A 

(sin7A - sin3A) - (sin5A - sinA) = 2sin2A(cos5A - cos3A) 

(cos7A + os3A - cos5A - cosA)/(sin7A - sin3A - sin5A + sinA)

= {2cos2A(cos5A - cos3A)}/{2sin2A(cos5A - cos3A)} 

= cot2A




suhaa6: 9..
suhaa6: hmm
suhaa6: ok
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