" 18."sin^(4)A-cos^(4)A=2sin^(2)A-1=1-2cos^(2)A=sin^(2)A-cos^(2)A" .IBihar "200

sin^4A-cos^4A=2sin^2A-1=1-2cos^2A=sin^2A-cos^2A

cos^(4)A-sin^(4)A=2cos^(2)A-1

cos^(4)A-sin^(4)A=2cos^(2)A-1

Prove the following identities: sin^(4)A-cos^(4)A=sin^(2)A-cos^(2)A=2sin^(2)A-1=1-2cos^(2)A

sin^(4)x+cos^(4)x=1-2sin^(2)x cos^(2)x

Prove the following identities: (sin+cos A)/(sin A-cos A)+(sin-cos A)/(sin A+cos A)=(2)/(sin^(2)A-cos^(2)A)=(2)/(2sin^(2)A-1)=(2)/(1-2cos^(2)A)

Prove that: (sin A + cos A)/(sin A - cos A) + (sin A - cos A)/(sin A + cos A) = (2)/(sin^(2)A-cos^(2)A)=(2)/(2sin^(2)A-1)=(2)/(1-2 cos^(2)A) .

Prove the following cos^(4)A-sin^(4)A+1=2cos^(2)A

sin A+sin^(2)A=1 then find cos^(2)A+cos^(4)A=

Prove that: ((1) / (sec ^ (2) A-cos ^ (2) A) + (1) / (cos ec ^ (2) A-sin ^ (2) A)) sin ^ (2) A cos ^ (2) A = (1-sin ^ (2) A cos ^ (2) A) / (2 + sin ^ (2) A cos ^ (2) A)