Maths

🎓 學業台小學及中學教育

Tsz

2007-03-08 5:22 am

3sinθ-cosθ=0

θ=幾呀
pls比步驟

thx a lot

回答 (2)

Null

2007-03-08 1:11 pm

✔ 最佳答案

3sinθ-cosθ=0
3sinθ=cosθ
sinθ/cosθ=1/3
tanθ=1/3
for θ between 0 and pi : θ=18.435
for θ between 0 and 2pi : θ=180+18.435=198.435

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用戶157343

2007-03-08 5:33 am

3sinθ-cosθ=0
3sinθ=cosθ
sinθ/cosθ=1/3
tanθ=1/3 <---因為sinθ/cosθ=tanθ
θ=18.1(corr. to 3 sig.fig)

2007-03-08 18:10:59 補充：
θ=18.4(corr. to 3 sig.fig)

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