" (b) "cos^(3)A cos3A+sin^(3)A sin3A=cos^(3)2A

Prove that : cos^(3)A cos3A+sin^(3)A sin3A=cos^(3)2A

Prove that : cos^3 A cos 3A + sin^3 A sin 3A = cos^3 2A

sin^(3)A sin3A+cos^(3)A cos3A=cos^(3)(2A)

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

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

If A = 30^(@) , show that : (i) (1 + sin 2A + cos 2A)/(sin A + cos A) = 2 cos A (ii) (cos^(3)A - cos 3A)/(cos A) + (sin^(3)A + sin 3A)/(sin A) = 3

Prove that cos ^ (3) and cos3e + sin ^ (3) and sin3e = cos ^ (3) 2e

Prove that: (cos^(3)A-cos3A)/(cosA)+(sin^(3)A+sin3A)/(sinA)=3

Prove that: (cos^(3)A-cos3A)/(cosA)+(sin^(3)A+sin3A)/(sinA)=3

If A=30^(@) , show that : (cos^(3)A-cos3A)/(cosA)+(sin^(3)A+sin3A)/(sinA)=3