Question

Rumus fungsi trigonometri

Answer 1

Identitas pythagoras
sin^2 x + cos^2 x = 1
1 + tan^2 x = sec^2 x
1 + cot^2 x = cosec^2 x
Identitas sudut ganda 
sin 2x = 2sinx.cosx
cos 2x = cos^2 x - sin^2 x atau
2cos^2 x -1 atau
1 - 2sin^2 x
Identitas Penambahan dan Pengurangan
sin(x+y) = sinx.cosy + cosx.siny
sin(x-y) = sinx.cosy - cosx.siny
cos(x+y) = cosx.cosy - sinx.siny
cos(x-y) = cosx.cosy + sinx.siny
tan(x+y) = (tanx + tany)/(1-tanx.tany)
tan(x-y) = (tanx - tany)/(1tanx.tany)
Identitas jumlah
sinx + siny = 2.sin((x+y)/2).cos((x-y)/2))
cosx + cosy = 2.cos((x+y)/2).cos((x-y)/2)
Identitas hasil kali
sinx.siny = -1/2[cos(x+y) - cos(x-y)]
cosx.cosy = -1/2[cos(x+y) + cos(x-y)]
sinx.cosy = -1/2[sin(x+y) + sin(x-y)]
semoga bermanfaat

Answer 2

Sin : depan / miring
Cos : samping / miring
Tan : depan / samping

Cosec : miring / depan
Sec : miring / samping
Cot : samping / miring