Jika AO = i + 2j, OB = 4i + 2j, dan sudut antara AO dan OB = ø maka tan ø ?
Matematika
Meirast
Pertanyaan
Jika AO = i + 2j, OB = 4i + 2j, dan sudut antara AO dan OB = ø maka tan ø ?
1 Jawaban
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1. Jawaban 4452mot
Jika AO = i + 2j, OB = 4i + 2j,
AO = i + 2j = (1, 2)
OB = 4i + 2j = (4, 2)
AO .OB = (1, 2) × (4, 2) = 4 + 4 = 8
|AO| = √(1)² + (2)² = √5
|OB| = √(4)² + (2)² = √20 = 2√5
Cos α = AO . OB / |AO| . |OB|
Cos α = 8 / (√5) × (2√5)
Cos α = 4/5
Tripel phytagoras 3, 4, 5
maka tan ø = 3/4