buktikan cos A x cotan A = cosec A - sin A

cos A cotanA
cos A × cos A / sin A
cos^2 A / sin A
(1 - sin^2 A)/sin A
1/sin A - sin^2 A / sin A
cosec A - sin A
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Bab Trigonometri
Matematika SMA Kelas X

cos a x cot a
= cos a x (cos a / sin a)
= (cos² a) / sin a
= (1 - sin² a) / sin a
= 1/sin a - (sin² a)/sin a
= cosec a - sin a

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