用MATLAB解题,谁会!

[a,b,c]=solve('343*a+2401*b+16807*c=4.5','3*a+28*b+245*c=0','a+28*b+490*c=0')
y=vpa(subs('a*x^3+b*x^4+c*x^5') ,5)%最后的那个5是保留5位数字的意思.不信你看yy
yy=subs('a*x^3+b*x^4+c*x^5')
ezplot(y)
运行结果：
a =.87463556851311953352769679300292e-1
b =-.15618492294877134527280299875052e-1
c =.71398821919438329267567085143095e-3

y =.87464e-1*x^3-.15618e-1*x^4+.71399e-3*x^5
yy =.87463556851311953352769679300292e-1*x^3-.15618492294877134527280299875052e-1*x^4+.71398821919438329267567085143095e-3*x^5