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 Question from Soham: Find out the value of the following: lim (x+x^2 +x^3 +.........x^n–n)/(x–1) x→1

Hi Soham,

Write the numerator as

$\left(x - 1\right) + \left(x^2 - 1\right) + \left(x^3 - 1\right) + \cdot \cdot \cdot + \left(x^n - 1\right).$

In the expression above each of the terms

$\left(x^k - 1\right)$

can be factored.

Can you complete the problem now?
Penny

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