Optimisation using the bisection method

**random_d** · 01-11-2015, 12:42 PM

Hi

I have to use the bisection method to optimise S to a minimum using the following equations:

S=4xh+2x((x^2)/4+b^2)^1/2 and h = V/(x^2) - b/3

V must be 20 and x must be 4

I have the following set up so that changing b changes the value of h and then S:
X1: 4
V1: 20
H1: =V1/(X1^2) - B1/3
S1: =4*X1*H1 + 2*X1*SQRT((X1^2)/4 + B1^2)

Any idea how to use the bisection method on excel so it finds the minimum value of S?
A shown excel page with all values in would be great and help me to see what is going on.

Thanks

**mrice** · 01-11-2015, 12:45 PM

Have you tried using the Solver functionality in Excel for this?

**MrShorty** · 01-11-2015, 01:17 PM

As I noted in your other thread: http://www.excelforum.com/excel-gene...-in-excel.html The Golden Search and bisection methods are very similar. The only real difference is in how you calculate x3 and f(x3) (and x4 and f(x4)). So before we repeat the suggestions given in the previous thread, how well did you do on the previous problem? What parts of programming the Golden search algorithm did you understand, and what parts do you still need help understanding? And, perhaps the $64 question, can you see how to change the golden search algorithm into the bisection algorithm?