Pembuktian Trigonometri 25 Poin

Bab Trignometri
Matematika SMA Kelas X

cos x : (tan x + sec x)
= cos x : (((sin x)/cos x) + 1/cos x)
= cos x : ((sin + 1)/(cos x))
= cos x . (cos x)/(1 + sin x)
= (cos² x) / (1 + sin x)
= (1 - sin² x) / (1 + sin x)
= ((1 - sin x) . (1 + sin x) / (1 + sin x))
= 1 - sin x

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