buktikan trigonometri berikut

3. (1/sin c -cos c /sin c ) (1 +cos c)
((1-cos c)/sin c) (1+cos c)
(1 -cos kuadrat c)/ sin c
Sin kuadrat c/ sin c = sin c (terbukti)

4.
sin A . Cos A (tan A + cotan A)=
SinA .Cos A (sin A/cosA+cos A/sin A)=
Sin A .CosA ((sin kuadrat A+ cos kuadratA)/sin A.cos A) = sin kuadratA + cos kuadrat A = 1 (terbukti)

Gak jelas tanyaaa. . . . .. .