Question

matlab求一元函数零点f=4.268x^3-4.987x^2+1.786x+2.039-2.23978在区间[0.2

Answer 1

f=@(x)4.268*x.^3-4.987*x.^2+1.786*x+2.039-2.23978;

>> x=fsolve(f,[0.2 0.36])

Equation solved.

fsolve completed because the vector of function values is near zero

as measured by the default value of the function tolerance,and

the problem appears regular as measured by the gradient.

x =

0.2432 0.3192

>> feval(f,x)

ans =

1.0e-008 *

-0.9783 -0.0001