Question

1-cos^4A/sin^4A=1+2cot^2A prove

Answer 1

Step-by-step explanation:

LHS

{1 - (cos^2A)^2} / (sin^2A)^2

a^2 - b^2 = (a+b)(a-b)

(1 - cos^2A)(1 + cos^2A) / (sin^2A)^2

we know that: sin^2A = 1 - cos^2A

= sin^2A(1 + cos^2) / sin^2A.sin^2A

= 1+cos^2A / sin^2A

= 1/sin^2A + cos^2A/sin^2A

= cosec^2A + cot^2A

formula - cosec^2A = 1 + cot^2A

= 1 + cot^2A + cot^2A

= 1 + 2cot^2A

Answer 2

Answer:

i dont know

Step-by-step explanation:

i dont know