Question

SOAL MATEMATIKA TRIGONOMETRI KELAS 11 SUSAH ABIS TOLONG BANTUANNYA! NO 8! KASIH POINT GEDE DAN TOLONG SERTAKAN CARA

Answer 1

(sin (90°-θ).cos (90°+θ))/tan (90°-θ)
= (sin (90°-θ).cos (90°+θ))/(sin (90°-θ)/cos (90°-θ)
= cos (90°-θ).cos (90°+θ)
= (cos 90°.cos θ + sin 90°.sin θ)(cos 90°.cos θ - sin 90°.sin θ)
= (0+sin θ)(0-sin θ)
= -sin² θ
= (cos 2θ-1)/2........opsi D