$\"\"$

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The electrical field strength xpression is $\"\"$ .

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If $\"\"$ is constant and $\"\"$ .

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Rewrite the $\"\"$ interms of one fraction.

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$\"\"$

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$\"\"$ .

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Find the transformation that relates $\"\"$ into $\"\"$ .

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Use the substitution $\"\"$ for $\"\"$ in $\"\"$ .

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Equate two function and solve for $\"\"$ .

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$\"\"$

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$\"\"$

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Thus, $\"\"$ .

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Replace $\"\"$ with $\"\"$ in $\"\"$ .

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$\"\"$ for $\"\"$ .

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$\"\"$ for $\"\"$ .

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$\"\"$ can be represented by power series $\"\"$ .

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$\"\"$

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$\"\"$ can be represented by power series $\"\"$ .