`(cos^3 A+sin^3 A) / (cos A+sinA)` + `(cos^3A-sin^3A) / (cos A-sin A) =2`

(cos3A+sin3A)/(cos A-sin A)=1+2sin2A

2sin A cos^(3)A-2sin^(3)A cos A=

2 sin A cos ^(3) A-2 sin ^(3) A cos A=

(cos A-cos3A) / (cos A) + (sin A + sin3A) / (sin A) =

8. (sin3A + sin A) sin A + (cos3A-cos A) cos A = 0

(sin3A + sin A) sin A + (cos3A-cos A) cos A = 0

sin4A=4cos^(3)A sin A-4sin^(3)A cos A

(sinA + sin3A) / (cosA + cos3A) = tanalpha, (cosA-cos2A) / (sinA + sin2A) = tanbeta, (sinA + sin3A + sin5A + sin7A) / (cosA + cos3A + cos5A + cos7A) = tan gamma , (cosA-cos5A-cos9A + cos13A) / (sinA-sin5A + sin9A-sin13A) = tandelta, then (a) alpha = 4beta (b) gamma = 2alpha (c) gamma = delta (d) none

The value of 2sinA cos^(3)A -2sin^(3)A cosA is

(sin A+sin3A)/(cos A+cos3A)=tan2A