cos x = 3/5
cari sisi depan (d)
d² = m² - s²
d² = 5² - 3²
d² = 25 - 9
d² = 16
d = √16
d = 4
sin x = d/m
sin x = 4/5
.
mencari sin 3x
sin 3x
= 3sin x - 4 sin³x
= 3(4/5) - 4(4/5)³
= 12/5 - 4(64/125)
= 12/5 - 256/125
= 300/125 - 256/125
= 44/125
..
maka:
sin 3x + sin x
= 44/125 + 4/5
= 44/125 + 100/125
= (44 + 100)/125
= 144/125
Penjelasan dengan langkah-langkah:
misal x = ß
cos ß = 3
5
rumus cos = x/r
x = 3
r = 5
y = √(5²–3²)
y = √(25–9)
y = √16
y = 4
rumus sin = y/r
sin ß = 4
Nilai dari sin 3ß + sin ß
= 2 sin (3ß + ß) cos (3ß – ß)
2 2
= 2 sin 4ß cos 2ß
= 2 sin 2ß cos ß
= 2(2 sin ß cos ß) cos ß
= 2 × (2 × 4 × 3 ) × 3
5 5 5
= 2² × 3² × 4
5³
" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
cos x = 3/5
cari sisi depan (d)
d² = m² - s²
d² = 5² - 3²
d² = 25 - 9
d² = 16
d = √16
d = 4
sin x = d/m
sin x = 4/5
.
mencari sin 3x
sin 3x
= 3sin x - 4 sin³x
= 3(4/5) - 4(4/5)³
= 12/5 - 4(64/125)
= 12/5 - 256/125
= 300/125 - 256/125
= 44/125
..
maka:
sin 3x + sin x
= 44/125 + 4/5
= 44/125 + 100/125
= (44 + 100)/125
= 144/125
Penjelasan dengan langkah-langkah:
misal x = ß
cos ß = 3
5
rumus cos = x/r
x = 3
r = 5
y = √(5²–3²)
y = √(25–9)
y = √16
y = 4
rumus sin = y/r
sin ß = 4
5
Nilai dari sin 3ß + sin ß
= 2 sin (3ß + ß) cos (3ß – ß)
2 2
= 2 sin 4ß cos 2ß
2 2
= 2 sin 2ß cos ß
= 2(2 sin ß cos ß) cos ß
= 2 × (2 × 4 × 3 ) × 3
5 5 5
= 2² × 3² × 4
5³
= 144
125