Nilai sin 10° + cos 170° =..... A. -1 B. -1/2 C. 0 D. 1

b. -1/2

klo salah maaf yah

Nilai fungsi

sin 10 + cos 170 =
= sin 10 + cos (90+80)
= sin 10 - sin 80
= - (sin 80 - sin 10)
= - {2 cos 45 sin 35)
= - {2 (1/2√2)(sin 35)}
= - √2 sin 35