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我们可以先将一个正弦用余弦的公式来代替,然后把式子化简一下:
2sin(x)*sin(x) = 1.5
sin^2(x) = 0.75
1 - cos^2(x) = 0.75(根据三角公式sin^2(x) + cos^2(x) = 1可知sin(x)的平方等于1减去cos(x)的平方)
cos^2(x) = 0.25
cos(x) = ±0.5
然后我们可以计算x了,根据余弦函数的周期性,x有两个解:
x = arccos(0.5) ≈ 60°
x = 2π - arccos(0.5) ≈ 300°
因此,方程2sin(x)*sin(x)=1.5的两个解分别是60度和300度。
Published at
2023-04-06 10:47:52Event JSON
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"content": "我们可以先将一个正弦用余弦的公式来代替,然后把式子化简一下:\n\n2sin(x)*sin(x) = 1.5\n\nsin^2(x) = 0.75\n\n1 - cos^2(x) = 0.75(根据三角公式sin^2(x) + cos^2(x) = 1可知sin(x)的平方等于1减去cos(x)的平方)\n\ncos^2(x) = 0.25\n\ncos(x) = ±0.5\n\n然后我们可以计算x了,根据余弦函数的周期性,x有两个解:\n\nx = arccos(0.5) ≈ 60°\n\nx = 2π - arccos(0.5) ≈ 300°\n\n因此,方程2sin(x)*sin(x)=1.5的两个解分别是60度和300度。",
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