Input argument "x" is undefined.function y=f(x) y=exp(-x)+exp(x);

Input argument "x" is undefined.function y=f(x) y=exp(-x)+exp(x);
Input argument "x" is undefined.function y=f(x) y=exp(-x)+exp(x);

Input argument "x" is undefined.function y=f(x) y=exp(-x)+exp(x);
没有定义变量x