Question

Trigonometri Kelas XI

Answer 1

Verified answer

Sin A = 45
sin B = 15

Answer 2

Jawab

A + B = 60
A - B = 30 ||(+)

2A = 90
A = 45

A + B = 60
45 + B = 60
B = 15

sin A sin B = sin 45 sin 15
= -1/2 ( -2 sin 45 sin 15)
= - 1/2 { cos (45+15) - cos(45-15)}
= -1/2  { cos 60 - cos 30)
= - 1/2 (1/2 - 1/2 √3)
=  -1/4  + 1/4 √3
= 1/4 (√3 - 1)