8- Which of the following counterexamples proves that csc xtan x = cos x is not a trignometric identity.

8- Which of the following counterexamples proves that csc xtan x = cos x is not a trignometric identity. Select all that apply

A) 0   B) pi÷4   C) pi÷3   D) 2pi

9- Which of the following possible trigonometric identities can be verified. Select all that apply

A) cosxtanx = sinx   B) tanxsecxsinx = 1   C) tanxcscxsinx = 1   D) cscxcotxsecx = csc^2 x

10- Which of the following possible trigonometric identities can be verified. Select all that apply

A) cotx + tanx = secxcscx    B) cotx + 2 = cosxcscx   C) sin^4 x – cos^4 x = 2sinx^2 x – 1    D) cotx÷sinx = cscx