Use the given information to find the exact value of the expression. a lies in quadrant I, and cos Ă - 7) sin a-- 17 A) 132 B) 468 493 493 Use trigonometric identities to find the exact value. 8) tan 25+ tan 5° 1-tan 25 tan 5* A) 2 B) 1/2 Ă lies in quadrant I C) 155 493 C) â3 Find cos (a +Ă). D) 475 493 D) â3 7) 8)