Temukan hasil dari cos 75?
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Penjelasan dengan langkah-langkah:
cos(75°) = cos(30° + 45°)
identitas trigonometri:
cos(a + b) = cos(a) cos(b) - sin(a) sin(b)
diketahui:
- a = 30°
- b = 45°
- cos(30°) = (√3)/2
- cos(45°) = (√2)/2
- sin(30°) = 1/2
- sin(45°) = (√2)/2
cos(30° + 45°) = cos(30°) cos(45°) - sin(30°) sin(45°)
cos(30° + 45°) = (√3)/2 × (√2)/2 - 1/2 × (√2)/2
cos(30° + 45°) = (√6)/4 - (√2)/4
cos(75°) = (√6 - √2)/4
