Jika sin x + cos x = -1/5, tentukan nilai tan 2x
Sin x + cos x = -1/5
(sin x + cos x)² = (-1/5)²
1 + sin 2x = 1/25
sin 2x = 1/25 – 1
sin 2x = -24/25
cos² 2x = 1 – sin² 2x
cos 2x = 7/25
tan 2x = sin 2x / cos 2x = -24/7
Jika sin x + cos x = -1/5, tentukan nilai tan 2x
Sin x + cos x = -1/5
(sin x + cos x)² = (-1/5)²
1 + sin 2x = 1/25
sin 2x = 1/25 – 1
sin 2x = -24/25
cos² 2x = 1 – sin² 2x
cos 2x = 7/25
tan 2x = sin 2x / cos 2x = -24/7