Diketahui Sin (A+B) = ¼ Sin (A-B) = 1/5 Tentukan nilai tan A cotangen B (Jelasin pake cara yah)

Sin(A+B) = sinAcosB + CosAsinB
Sin(A-B) = sinAcosB - CosAsinB
___________________________ +
sin(A+B) + sin(A-B) = 2sinAcosB
1/4 + 1/5 = 2sinAcosB
5/20 + 4/20 = 2sinAcosB
9/20 = 2sinAcosB ........ (1)

Sin(A+B) = sinAcosB + CosAsinB
Sin(A-B) = sinAcosB - CosAsinB
___________________________ _
sin(A+B) - sin(A-B) = 2coaAsinB
1/4 - 1/5 = 2cosAsinB
5/20 - 4/20 = 2cosAsinB
1/20 = 2cosAsinB ........(2)

dari (1) dan (2)
2sinAcosB/2cosAsinB = (9/20)/(1/20)
tanAcotB = 9/20 × 20/1
tanAcotB = 180/20
tanAcotB = 9

smoga mmbantu