Roots of an equation

[Mightyducks85]

I really don't understand this one.

To determine the roots of the equation x^2 + x -1 = 0, Andrea started with a guess of x(sub 1) = 1/2. Is her initial guess reasonable? Justify your answer by stating a theorem. What was her answer for x(sub 2)?

 

[stapel]

I have a feeling they're wanting you to review Newton's Method...? :wink:

 

[BigGlenntheHeavy]

\(\displaystyle x = \frac{-b \ + \ or \ - \ [b^{2}-4ac]^{1/2}}{2a}, \ (Quadratic \ Formula).\)

\(\displaystyle For \ f(x) = x^{2}+x-1 = 0, \ a = 1, \ b = 1, \ and \ c = -1.\)

\(\displaystyle Can \ you \ take \ it \ from \ here?\)

 

[daon]

\(\displaystyle x = \frac{-b \ + \ or \ - \ [b^{2}-4ac]^{1/2}}{2a}, \ (Quadratic \ Formula).\)

\(\displaystyle For \ f(x) = x^{2}+x-1 = 0, \ a = 1, \ b = 1, \ and \ c = -1.\)

\(\displaystyle Can \ you \ take \ it \ from \ here?\)

You can use "\pm" to get \(\displaystyle \pm\).

 

[Deleted member 4993]

I really don't understand this one.

To determine the roots of the equation x^2 + x -1 = 0, Andrea started with a guess of x(sub 1) = 1/2. Is her initial guess reasonable? Justify your answer by stating a theorem. What was her answer for x(sub 2)

What "method of estimation" are you supposed to check for x[sub:6dm40use]2[/sub:6dm40use]?

?

 

[BigGlenntheHeavy]

Thank you daon.