`cos^4A-sin^4A` is equal to `2cos^2A+1` (b) `2cos^2A-1` (c) `2sin^2A-1` (d) `2sin^2A+1`

cos^4A-sin^4A is equal to (a) 2cos^2A+1 (b) 2cos^2A-1 (c) 2sin^2A-1 (d) 2sin^2A+1

cos^(4)A-sin^(4)A is equal to 2cos^(2)A+1(b)2cos^(2)A-1(c)2sin^(2)A-1( d) 2sin^(2)A+1

17*cos^(4)theta-sin^(4)theta is equal to (a)1-2sin^(2)((theta)/(2))(b)2cos^(2)theta-1(c)1+2sin^(2)((theta)/(2))(d)1+2cos^(2)theta

Show that : Cos^4A - Sin^4A = Cos^2A - Sin^2A = 2 Cos^2A - 1

If sinA+sin^2A=1, then the value of cos^2A+cos^4A is

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) .

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

If (cos^4A)/(cos^2B)+(sin^4A)/(sin^2B)=1 then prove that (cos^4B)/(cos^2A)+(sin^4B)/(sin^2A)=1

cos^4theta- sin^4theta is equal to.............. (a) 1 -2 sin^2(theta/2) (b) 2cos^2theta-1 (c) 1+2sin^2(theta/2) (d) 1+2cos^2theta