Flag Trigonometry> (SinA + Sin3A + Sin5A + Sin7A)/(CosA + Co...
question mark

(SinA + Sin3A + Sin5A + Sin7A)/(CosA + Cos3A + Cos5A + Tan7A) = tan 4A

Anil Karira , 5 Years ago
Grade 12th pass
anser 2 Answers
Saurabh Koranglekar
Dear student

Please write complete question is it to prove or finding value of A

Regards
Last Activity: 5 Years ago
Aditya Gupta
(sinA+sin3A+sin5A+sin7A)/(cosA+cos3A+cos5A+cos7A)
=(sinA+sin7A)+(sin3A+sin5A)/(cosA+cos7A)+(cos3A+cos5A)
=(2sin4Acos3A+2sin4AcosA)/(2cos4Acos3A+2cos4AcosA) (using sinx + siny= 2sin(x+y)/2cos(x – y)/2 and cosx + cosy= 2cos(x+y)/2cos(x – y)/2)
=2sin4A(cos3A+cosA)/2cos4A(cos3A+cosA)
=sin4A/cos4A
=tan4A 
hence proved
KINDLY APPROVE :))
Last Activity: 5 Years ago
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments