False position method problem

[jendrin]

I just want to ask if there is no sign change how can i solve it?
my problem is: sinx + cos(1 + x^2) -1
Xi=3 Xi-1= 1
I tried solving it first manually before making a program of it..

[sanctus]

I just want to ask if there is no sign change how can i solve it?
my problem is: sinx + cos(1 + x^2) -1
Xi=3 Xi-1= 1
I tried solving it first manually before making a program of it..

what are the equations you want to solve (i.e. sin(x)+cos(1+x^2)-1
=????) ? What is the relation between x and Xi?

[Meetee]

I just want to ask if there is no sign change how can i solve it?
my problem is: sinx + cos(1 + x^2) -1
Xi=3 Xi-1= 1
I tried solving it first manually before making a program of it..

Hi,

You want to put the values of x in sinx + cos(1 + x^2) -1 equation to get answer?

Kindly elaborate your problem as the information given in your post is not enough to solve your problem.

Regards

[JosAH]

Hi,

You want to put the values of x in sinx + cos(1 + x^2) -1 equation to get answer?

Kindly elaborate your problem as the information given in your post is not enough to solve your problem.

Regards

I recognize that equation; most likely the OP wants to find an approximation
of a root of that equation. Using the secant method you need two initial approximations
one for which f(x1) < 0 and one for which f(x2) > 0. I think the question is: what
to do when the sign of both those function values are equal? I'd say: you can't
use that method then.

kind regards,

Jos

[jendrin]

thx josh. so can i just say "root can't be solved"? the max iterations for secant method is 4times to get the 1st postive root. can i just change the number of iterations ?

[JosAH]

thx josh. so can i just say "root can't be solved"? the max iterations for secant method is 4times to get the 1st postive root. can i just change the number of iterations ?

Since the signs of the function values of both Xi and Xi-1 are equal you can't
use those two values as initial approximations for the root value; at least you
can't use the secant method here. That's all there is to it. You either have to
find two other Xi, Xi-1 values or you have to use another approximation method.

kind regards,

Jos