余弦波计算 JAVA中如何进行正弦和余弦的计算
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\u6240\u4ee5\uff1aarccos0.65=49.458398126495478241087466719172.......
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java.lang.Math\u7c7bMath\u4e2d\u7684\u65b9\u6cd5double b;b=sin(double a) \u8fd4\u56dea\u89d2\u7684\u4e09\u89d2\u6b63\u5f26\u3002b=cos(double a) \u8fd4\u56dea\u89d2\u7684\u4e09\u89d2\u4f59\u5f26\u3002
Acos（wt + u) +Bcos(wt + z)=A(coswtcosu-sinwtsinu)+B(coswtcosz-sinwtsinz)
=(Acosu+Bcosz)coswt-(Asinu+Bsinz)sinwt
=(1/((Acosu+Bcosz)^2+(Asinu+Bsinz)^2)^(1/2)cos(wt+m)
=Ccos(wt+m)
即为所求
其中C=(1/((Acosu+Bcosz)^2+(Asinu+Bsinz)^2)^(1/2)
=(A^2+B^2+2ABcos(u-z))^(1/2)
cosm=(Acosu+Bcosz)/C, sinm=(Asinu+Bsinz)/C
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