怎么解方程cos(x)+sin(x)=0 ？
\u600e\u4e48\u7528matlab\u6c42\u89e3cos(x)-x*sin(x)=0\u5e76\u753b\u51fay=cos(x)-x*sin(x)\u7684\u56fe\u50cf\uff1f\u5728\u7ebf\u7b49\uff0c\u6025\u7528\uff01\uff01ezplot('cos(x)-x*sin(x)') %\u753b\u51fa\u56fe\u50cf
fzero('cos(x)-x*sin(x)',x0) %x0\u662f\u4f60\u6839\u636e\u56fe\u50cf\u731c\u7684\u6839\uff0c\u51fd\u6570\u8fd4\u56de\u8be5\u503c\u9644\u8fd1\u7684\u96f6\u70b9
ezplot\u9ed8\u8ba4\u7684\u8303\u56f4\u662f[-2*pi,2*pi]\uff0c\u662f\u67094\u4e2a\u96f6\u70b9\u3002\u4f60\u5206\u522b\u731c\u4e00\u4e0b\u5c31\u53ef\u4ee5\u4e86\u3002\u6216\u8005\u53ef\u4ee5\u5199\u4e2afor\u5faa\u73af
for k=[-3,-1,1,3]
fzero('cos(x)-x*sin(x)',k)
end
\u8fd9\u4e2a\u5df2\u7ecf\u4e0d\u662f\u7ebf\u6027\u65b9\u7a0b\u7ec4\u4e86\uff1a
clear all;clc;
[x,y]=solve('x-0.7*sin(x)-0.2*cos(y)','y-0.7*cos(x)+0.2*sin(y)','x','y')
x =
.52652262191818418730769280519209
y =
.50791971903684924497183722688768
如下图所示：望采纳~如有疑问可以追问。
cos(x)=-sin(x),1=-sin(x)/cos(x)=-tan(x)=1。。。x=-3/2∏+360°
化简啊 或者每个都等于0
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