tan^2 330度-sin^2(-100度)-cos^2 460度
in full step
F4 Maths
2012-04-28 5:49 am
回答 (3)
2012-04-28 6:10 am
✔ 最佳答案
圖片參考：http://latex.codecogs.com/gif.latex?\begin{align*}%20tan^2330-sin^2(-100)-cos^2460%20&=(-tan30)^2-(cos10)^2-(sin10)^2%20\\%20&=%20tan^230-(cos^210+sin^210)\\%20&=%20tan^230-1\\%20&=%20\frac{\sqrt{3}}3{}-1\\%20\end{align*}
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參考: 神風亨
2012-04-28 7:09 am
tan^2 330度-sin^2(-100度)-cos^2 460度
=tan^2(360-30)+sin^2(100)-cos^2(360+100)
=-tan^2 30+sin^2 100+cos^2 100
=1-√3/3
=tan^2(360-30)+sin^2(100)-cos^2(360+100)
=-tan^2 30+sin^2 100+cos^2 100
=1-√3/3
2012-04-28 6:13 am
it is wrong
the ans is -2/3
the ans is -2/3
收錄日期: 2021-04-13 18:39:09
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