`cos4A=1-8cos^2A+8cos^4A`

Prove that cos 4A=1-8cos^2A+8 cos^4A

Prove that: cos4A=1-8cos^(2)A+8cos^(4)A

Prove that: cos4A=1-8cos^2\ A+8cos^4\ A

cos4 alpha=1-8cos^(2)alpha+8cos^(4)alpha

If sin A+sin^(2)A+sin^(3)A=1, then find the value of cos^(6)A-4cos^(4)A+8cos^(2)A

If sin A + sin^2 A + sin^3 A = 1 , then find the value of cos^6 A-4 cos^4 A + 8 cos^2 A .

If sin A + sin^2 A + sin^3 A = 1 , then find the value of cos^6 A-4 cos^4 A + 8 cos^2 A .

If sin A + sin^2 A + sin^3 A = 1 , then find the value of cos^6 A-4 cos^4 A + 8 cos^2 A .

Prove that cos A cos 2A cos 4A cos 8A= (sin 16A)/(16 sin A) .

If A is not an integral multiple of (pi) , prove that cos A cos 2A cos 4A cos 8A =(sin 16A)/(16 sin A) Hence deduce that cos. (2pi)/(15). Cos. (4pi)/(15) .cos. (8pi)/(18). Cos. (16pi)/(15)=(1)/(16)