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## Homework Statement

Hi, I going through my class notes for a fluids class, specifically fundamental solutions of the Stokes equations. To derive the stresslet and rotlet involves solving the following

u

_{i}= (1/8*pi*μ)*(∂G

_{ik}/∂x

_{j})*F

_{k}*A

_{j}

G

_{ik}(x) = δ

_{ij}*(1/r)+(x

_{i}x

_{j}/r

^{3})

We looked at it in a lecture (skipping all the "easy parts"!! of course) and I am trying to fill in the gaps. The first step is to taylor expand it at A/2 wit |A/2| << |x|.

This should give u

_{i}(

**x**) = (1/8*pi*μ)*(G

_{ik}(

**x**-

**0**)F

_{k}+ (A

_{i}/2)*∂/∂x

_{j}(G

_{ik})(

**x**-

**0**)*F

_{k}+ ... (Mix of vector and suffix notation here very confusing)

Then do the same at -A/2 (with -F) and add the solutions

## Homework Equations

Taylor series: f(a) + f'(a)*(x-a) + (f''(a)/2!)*(x-a)

^{2}+ ....

## The Attempt at a Solution

My problem is the mix of notation, I am not sure how to apply the taylor series here. Any help appreciated.