Diketahui A dan B sudut tumpul. Jika sin A =1/2√2 dan sin B=3/5 ,maka nilai sin (A+B)=

sinA = 1/2akar(2) = 45°
cosA = 45° = 1/2akar(2)
sinB = 3/5 = 37°
cosB = 37° = 4/5

sin (A + B) = sinA.cosB - cosA.sinB
sin (A + B) = 1/2akar(2).4/5 - 1/2akar(2).3/5
sin (A + B) = 4/10akar(2) - 3/10akar(2)
sin (A + B) = 1/5akar(2)