Posted by **Anonymous** on Tuesday, June 1, 2010 at 7:03pm.

You are using Newton's method to solve

e^x - 2. If you first guess is x1=1, what value will you calculate for the next approximation x2?

...I don't know what Newton's method is, so I looked it up...and I'm still confused. Help plz?

Thx

- Calculus -
**Reiny**, Tuesday, June 1, 2010 at 8:03pm
first of all, to "solve" we need an equation.

You have the expression e^x - 2

Are you solving e^x - 2 = 0 ?

I will assume you are.

let f(x) = e^x - 2

f ' (x) = e^x

Newton's method says ...

x_{n+1} = x_{n} - f(x_{n})/f ' (x_{n})

so x_{2} = 1 - (e^1 - 2)/e^1

= .73576

x_{3} = .73576 - (e^.73576 - 2)/e^.73576 = .69404

x_{4} = .69404 - (e^.69404 - 2)/e^.69404 = .69314758

notice we are rapidly approaching some kind of fixed value.

If the value of x of our input returns as output, we have the solution.

A most remarkable procedure.

Using logs I get x = .69314718 , so our method was accurate to 6 digits after only 3 iterations.

## Answer This Question

## Related Questions

- calculus - You are using Newton's method to solve x^3-5x-2=0. If your first ...
- Grade 12 AP calculus - You are using Newton's method to solve x3-5x-2=0. If your...
- Calculus-Newton Method Approximation - Use Newton's method to approximate the ...
- calculus - Use Newton's method to solve the equation sec x = 4 in the interval x...
- Calculus 1 Newton's Method - Using Newton's method, approximate the root of the ...
- Calculus I - Using Newton's Method, determine the first approximation to the ...
- calculus, math - Use Newton's method to approximate the value of (543)^(1/5) as ...
- Math/ Calculus - Given an initial guess of x1 = 1, use the Newton-Raphson Method...
- calculus - Use Newton's method to approximate a root of the equation 3sin(x)=x ...
- calculus - Use Newton's method to approximate a root of the equation 3sin(x)=x ...

More Related Questions