Diketahui sin A = 12/13 tentukan nilai dari cos A dan tan A

Misalkan, buat seg siku2 di B
Sin A = Depan /  Miring
Sin A = BC/AC
BC = 12
AC = 13
maka AB = 5

cos A = 5/13
Tan A = 12/5

Misal:
Depan = a
Samping = b
Miring = c

Dik:
sin A = depan/miring = 12/13
depan (a) = 12
miring (c) = 13

Jwb:
Cari dulu "samping" nya, gunakan rumus pytagoras

b = √(c² - a²)
b = √(13² - 12²)
b = √(169 - 144)
b = √25
b = 5

Jadi,
Cos A = samping/miring = 5/13
Tan A = depan/samping = 12/5