Question

Buktikan 2 - sin^2 x/ cos x = sec x + cos x

Answer 1

2-sin^2 x / cosx = secx + cosx
2-(1-cos^2 x) / cosx = 1/cosx + cosx
2-1+cos^2 x / cos x = 1+cos^2 x / cosx
1+cos^2 x =1+cos^2 x

Answer 2

Ingat bahwa :
sin²x = 1 - cos²x
1/cos x = sec x

maka :

2 - sin² x / cos x = sec x + cos x
2 - (1 - cos² x) / cos x = sec x + cos x
1 + cos² x / cos x = sec x + cos x
1/cos x + cos²x / cos x = sec x + cos x
sec x + cos x = sec x + cos x  ⇒ terbukti