a.Cos 45 derajat+cos 60 derajat b.sin 45 derajat ×cos 30 derajat + cos 60 c. tg 30 derajat-sin 120 derajat

a. 1/2 √2 + 1/2 = 1/2 ( √2+1 )
b. 1/2 √2 x 1/2 √3 + 1/2 = 1/4 √6 + 1/2 = 1/2 (1/2√6 + 1)
c. 1/3 √3 - 1/2 √3 = -1/6 √3