Prove the trigonometric identities. 2 cosθ sinθ / tan(90°- θ) ≡ 2sin²θ?
回答 (2)
2017-08-12 2:18 am
✔ 最佳答案
2 cosθ sinθ / tan(90°- θ)=2 cosθ sinθ / (1 / tanθ)
=2 cosθ sinθ tanθ
=2 cosθ sinθ × sinθ/cosθ
=2sin²θ
2017-08-11 5:15 pm
Prove the trigonometric identities. 2CosθSinθ/Tan(90°-θ)≡2Sin^2 θ?編輯
Sol
2CosθSinθ /Tan(90°-θ)
=2CosθSinθ /Cotθ
=2CosθSinθ /(Cosθ/Sinθ)
=2Sin^2 θ
Sol
2CosθSinθ /Tan(90°-θ)
=2CosθSinθ /Cotθ
=2CosθSinθ /(Cosθ/Sinθ)
=2Sin^2 θ
收錄日期: 2021-04-24 00:38:42
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