sin 20° × sin 240° × tan 45°/cos 70° × cos 120° × tan 120° =
Matematika
riska240201
Pertanyaan
sin 20° × sin 240° × tan 45°/cos 70° × cos 120° × tan 120° =
1 Jawaban
-
1. Jawaban vyalovya
Sin 20° × sin 240° × tan 45°/(cos 70° × cos 120° × tan 120°)
= Sin 20° × sin (180+60°) × tan 45°/(sin(90-70°) × cos (180-60°) × tan (180-60°))
= Sin 20° × -sin 60° × tan 45°/(sin 20 × -cos 60° × -tan 60°)
= -sin 60° × tan 45°/(cos 60° × tan 60°)
= -√(3)/2 × 1 / (1/2 × √(3))
= -√(3)/2 / (√(3)/2)
= -1