tolong dibantu no 1,3,4 ya

1. sin a = 6/10
sisi depan 6
sisi miring 10
sisi samping 8
cos a = samping/miring = 8/10

3. sin²a + cos²b = 1 (identitas trigonometri)
sin²45 + cos²b = 1

4. cos a = 7/25
sisi samping 7
sisi depan 24
sisi miring 25
sin a = depan/miring = 24/25