- #1

DryRun

Gold Member

- 838

- 4

## Homework Statement

Solve for positive root of equation: 10 + 3x^2 = e^x

## Homework Equations

The usual Newton-Raphson formula.

## The Attempt at a Solution

f(x) = 10 + 3x^2 - e^x

f'(x) = 6x -e^x

But then my biggest problem, how to find the initial guess? I have looked around, and i can't find a definitive answer on how to find the initial value. From what i understand, i can plot a graph and then look for an estimate. Is that the best method there is?

Anyway, i plotted a graph and i have no idea how to interpret it, as the two curves don't touch on my graph paper, so i can't figure out an estimate. I get a curve with minimum 3x^2 + 10 and the graph of e^x. Is that correct?