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grei
Posts:
132
Registered:
11/27/12


Re: Help with Newton Raphson equation
Posted:
Nov 27, 2012 10:08 AM


Do you not know what "Newton Raphson" is? You are asked to solve 4x^4 2x^3+ 5= 0 using Newton Raphson with initial value x= 2.
The "Newton Raphson" method is to, given a starting x_n, find the next x_(n+1)= x_n f(x_n)/f'(x_n).
Here, f(x)= 4x^4 2x^3+ 5 and f'(x)= 16x^3 6x. With x= 2, f(2)= 4(16) 2(8)+ 5= 64 16+ 5= 43 and f'(2)= 16(8) 6(2)= 128 12= 116.
That is, with x1= 2, x2= 2 43/116= 1.63.
Now what is x2?



