Hasil dari Sin 75° + Sini 15°=

Jawaban:

sin 75 = sin (45 + 30)

sin (45 + 30) = sin45 × cos30 + cos45 × sin30

sin (45 + 30) = ½√2 × ½√3 + ½√2 × ½

sin (45 + 30) = ¼√6 + ¼√2

sin (45 + 30) = ¼ [√6 + √2]

Jadi, sin 75 = ¼ [√6 + √2]

sin 15 = sin (45 – 30)

sin (45 – 30) = sin45 × cos30 – cos45 × sin30

sin (45 – 30) = ½√2 × ½√3 – ½√2 × ½

sin (45 – 30) = ¼√6 – ¼√2

sin (45 – 30) = ¼ [√6 – √2]

Sehingga, sin 15 = ¼ [√6 – √2]

sin 75+sin 15 = √6+√2/4+√6-√2/4

= √6+√6-√2+√2/4

=√6+√6/4

= 2√6/4

= √6/2