Question

C

Q. use the following exact value for diagram to find an Sin 72° 27 4-28 36 720 36

Answer 1

Solution DH A22 In A B C D and DACO LBCD = LACD=369 Similarly So sides BD = 1 -* ( equal anglês opposite sides are also equal) And, In A ABC LACB = ABC= 72 So, sides AB = 1 (Opposite rices op - 1 equal angle) 4-2x+22=4 (4=4)- AC

by ④ equation 4-22=22 4 = 42 = =Tu= 1 Hence sides of A ABC are as follows A B = 4, AC=4 and Bo=2

4 Sin 72 = Sin (36+36) sin 36=√10-252 sin72 = 2 2 5 10-252 Singe - 19-253 = 0.253823362 2