Question

Quiz Math
Buktikan identitas trigonometri berikut.

Answer 1

Verified answer

Kelas 10 Matematika
Bab Trigonometri

Cara 1 
1] tan α/2 = (sin α)/(1 + cos α)

cot α/2 = 1/(tan (α/2))
cot α/2 = 1/((sin α) / (1 + cos α))
cot α/2 = (1 + cos α)/(sin α)

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Cara 2
cot α/2 = (cos (α/2)) / (sin (α/2))
cot α/2 = √((1 + cos α)) / √((1 - cos α)/2)
cot α/2 = √((1 + cos α)/(1 - cos α) . (1 + cos α)/(1 + cos α))
cot α/2 = √((1 + cos α)²/(1 - cos² α))
cot α/2 = √((1 + cos α)² / sin² α)
cot α/2 = (1 + cos α)/sin α

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