怎么求sin(x)/cos(x)
1、对于简单的三角方程，可以用solve()来求解，得到解析解。如
其求解代码和结果为
2、对于复杂的三角方程，可以用Broyden（拟牛顿法）等方法来求解，得到数值解。如
其求解过程如下
①建立自定义函数文件，funm。m
function y = funm(x)
%x=x(1,1)，y=x(2,1)
y(1,1) = x(1,1) - 0.7 * sin(x(1,1)) - 0.2 * cos(x(2,1));
y(2,1) = x(2,1) - 0.7 * cos(x(1,1)) + 0.2 * sin(x(2,1));
end
②编写Broyden文件，Broyden。m
③在命令窗口输入
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绛旓細涓汉鎰熻杩欎釜鏄嚜宸辨兂鍑烘潵鐨勫紡瀛愶紝鏍规湰灏辨病鏈夎繖绉嶈〃绀烘柟娉曪紝杩欎篃涓嶆槸澶嶅悎鍑芥暟姹傚锛屾嫭鍙锋槸涓嶅簲璇ュ瓨鍦ㄧ殑锛岃嫢y=sin锛坸锛锛屽垯鍙眰寰梮=arcsiny. 鍙坹=sinx锛屽悓鏍峰緱鍒皒=arcsiny. 鍙帹寰楋紙x锛=x锛屽叾瀹炲氨鏄痽=sinx锛屽鏁皔'=cosx
绛旓細f(x)=sin(2x+蟺/6)+½T=2蟺/2=蟺 浜旂偣锛歠(-蟺/12)=0.5,f(蟺/6)=1.5,y(5蟺/12)=0.5,y(2蟺/3)=-0.5 y(11蟺/12)=0 鐢眣=sin(x)鐨勫浘鍍忥紝姘村钩鏂瑰悜鍘嬬缉鍒颁竴鍗婏紝鐒跺悗灏嗗浘鍍忔暣浣撳悜宸﹀钩绉幌/6锛屽啀鍚戜笂鏁翠綋骞崇Щ½涓崟浣嶅氨鍙緱鍑哄嚱鏁扮殑銆
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