math help
回答 (2)
2008-01-20 6:51 am
✔ 最佳答案
sinx(cos²x- 2 )=0sinx = 0 or cos²x-2=0
sinx = 0 or cosx=+-(開方2)
x=0°or = 180°or 360°, cosx果邊=error,因為cosx一定係-1至1之間
so得3個解
參考: 自己
2008-01-20 6:50 am
sinx=0
x=0,180,360
cos²x- 2 =0(rejected)
x=0,180,360
cos²x- 2 =0(rejected)
收錄日期: 2021-04-16 22:14:51
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