Pertanyaan

S in 2 0 ∘ + cos 6 ∘ = ....

$S in 2 0^{\circ} + cos 6^{\circ} = ....$

N. Rahayu

Master Teacher

Mahasiswa/Alumni Universitas Negeri Jakarta

Jawaban terverifikasi

Pembahasan

Rumus yang akan dipakai diantaranya sebagai berikut: Sehingga penyelesaian di atas akan didapat:

Rumus yang akan dipakai diantaranya sebagai berikut:

$begin mathsize 14px style 2 space cos space alpha space cos beta space equals space cos open parentheses fraction numerator alpha plus beta over denominator 2 end fraction close parentheses plus cos open parentheses fraction numerator alpha minus beta over denominator 2 end fraction close parentheses end style$

Sehingga penyelesaian di atas akan didapat:

$begin mathsize 14px style S i n space 20 degree plus space cos space 6 degree space equals space cos space open parentheses 90 minus 20 close parentheses degree plus cos space 6 degree space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals space cos space 70 degree plus cos space 6 degree space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals space 2 space cos space open parentheses fraction numerator 70 degree plus 6 degree over denominator 2 end fraction close parentheses space cos space left parenthesis fraction numerator 70 degree minus 6 degree over denominator 2 end fraction right parenthesis space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals space 2 space cos space 38 degree space cos space 32 degree end style$