How do I Taylor expand the gravitational field in terms of h/R <<1?

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To perform a Taylor expansion of the gravitational field in the context of h/R << 1, start by rewriting the gravitational field equation as G(r) = -GM(R+h)/(R+h)^3. This can be simplified to G(r) = -GM/R^2 * (h/R + 1)^(-2). A Taylor series expansion of the function f(x) = (x+1)^(-2) around x = 0 is necessary to proceed. The first-order approximation leads to the gravitational force F being expressed as F ≈ mg e_z, where g is defined in terms of R and M. The discussion also seeks to identify the first h-dependent correction to the gravitational force.
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Homework Statement


Consider the position vector of a mass m at height h above the Earth's surface to be \underline{r}=(R+h)\underline{e}_z where R is the radius of the Earth.
Make a Tylor expansion in h/R <<1 of the gravitational field
\underline{G}(\underline{r})=\frac{-GM\underline{r}}{r^3}
to show that the gravitational force on a mass m can be written as \underline{F} \approx mg\underline{e}_z giving an expression for g in terms of R and M, the mass of the Earth.
Find the first correction (h-dependent) to the gravitational force.

Homework Equations

The Attempt at a Solution


I am having trouble understanding how to expand the function in h/R<<1.

We can rewrite \underline{G}(\underline{r})=\frac{-GM(R+h)}{(R+h)^3}\underline{e}_z which then can then be expressed as \underline{G}(\underline{r})=\frac{-GM}{R^2}(\frac{h}{R}+1)^{-2}\underline{e}_z
I am not sure how to proceed with the expansion.
Any explanation will be appreciated.
 
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Let ##x = h/R##. You need to make a Taylor series expansion of the function ##f(x) = (x+1)^{-2}##.
 
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