9 6 Find the n Graph the fol wing 9 If A and R are acute ang

#9

6. Find the n Graph the fol wing 9. If A and R are acute angles sach than cso ord ca B -s. sec 24 and tan 2B. 10. Find the area of the largest rectangle thai van be ms m new ctn and 4 cm if two sides of the rectangie alerg the regs as

Solution

cscA = 5/3

cos A = 3/5

sin A = 4/5

cosB = 8/17

sin B = 15/17

sec 2A = 1/cos2A = 1/(1 – 2 sin²(A) ) = 1/[1 - 32/25] = -25/7

tan 2B = sin 2B/cos 2B = 2*sinB*cosB/(1 - 2 sin²B) = (240/289)/(-161/289) = -240/161