Which of the following are identities? check all that apply. a. sin^2x - cos^2x = 1 b. sin^2x = 1 - cos^2x c. tan^2x = 1 + sec^2x d. cot^2x = csc^2x - 1

Option B and D are correct

Step-by-step explanation:

Option A is incorrect because the  correct  identity we have is

Hence, Option A is incorrect

Option B is correct because we have an identity

Hence, Option B is correct

Option C  is incorrect because we have an identity

   not  

Hence, Option C is incorrect

Option D is correct because we have an identity

  which implies  

Hence, Option D is correct.

i believe the answer is c.