solve错在哪里？？ 求助！！！

[debateshang]

我的意思是你这种设法有问题，可能matlab中无法处理
solve('a*b-d*exp(x-3)+exp(-4*x+2)=0','x');
??? Error using ==> solve at 162Unable to find closed form solution.
解这个方程matlab都解不出解析解，字母太多在matlab里可能就没法讨论了
这就像五次方程没有一般系数解
solve('a*x^5+b*x^4+c*x^3+d*x^2+m*x+n','x');
??? Error using ==> solve at 162
Unable to find closed form solution.
但是
solve('3*x^5+1*x^4+2*x^3+4*x^2+2*x+1')

ans =

.50436452606242968189338746040867+1.0358328721587116228614551628226*i
-.23178710110867900315683730233415+.48181007825073643046183194749188*i
-.87848818324083469080643364948239
-.23178710110867900315683730233415-.48181007825073643046183194749188*i
.50436452606242968189338746040867-1.0358328721587116228614551628226*i
就能解