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Verify the identity. cot 2 =cot tesc t cos t Which of the following four statements establishes the identity? OA. cot sin t = cot t cos t coS t =cot tesc t COS t OB. cot 2 t cos t = cot t cos t sin t =cot tesc t COS OC. cott cos t = cot t cos t sin t =cot tesc t sin t OD. 2 cot sin t =cot t cos t =cot tesc t coS t sin tVerify the identity. sin 0 . sec 0. cot 0=1 Which of the following four statements establishes the identity? COS O O A. sin 0 . sec 0 . cot 0= sin 0. = 1 sin 0 sin 0 1 coS O O B. sin 0 . sec 0 . cot 0= sin 0. - coS O = 1 sin 0 1 sin 0 O C. sin 0 . sec 0 . cot 0= sin 0. - coS O =1 coS O 1 sin 0 O D. sin 0 . sec 0. cot 0= sin 0. =1 sin 0 COS OWrite the expression as the sine, cosine, or tangent of an angle. Then find the exact value of the expression. sin 20 cos 10 + cos 20 sin 10 Rewrite the expression using a sum or difference formula. Choose the correct answer below. O A. sin (20 + 10) O B. cos (20' + 10") O c. cos (200 - 10") O D. sin (209 - 109) Write the expression as the sine, cosine, or tangent of an angle. sin 20 cos 10 + cos 20 sin 10* = (Type an exact answer, using it as needed. Use integers or fractions for any numbers in the expression.) Find the exact value of the expression. sin 20 cos 10 + cos 20 sin 10 =] (Simplify your answer. Type an exact answer, using radicals as needed. Use integers or fractions for any numbers in the expression. Rationalize all denominators.)Write the expression as the sine, cosine, or tangent of an angle. Then find the exact value of the expression. tan 10" + tan 50 1 - tan 10" tan 50 Rewrite the expression using a sum or difference formula. Choose the correct answer below. O A. tan (108 + 50") O B. cos(10' + 50") O c. sin(10 - 50") O D. tan (109 -50") Write the expression as the sine, cosine, or tangent of a single angle. tan 10 + tan 50 1 - tan 10 tan 50 = Find the exact value of the expression. tan 10 + tan 50 1 - tan 10 tan 50 (Type an exact answer in fraction format, using radicals as needed, and rationalize any denominator.)