Binomial Expansion

EasyMedium
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Question 46
Medium

The signal noise N N\,N in a high-precision sensor is modeled by the function N(c)=(3+c4)9\displaystyle N(c) = \left(3 + \frac{c}{4}\right)^9N(c)=(3+4c​)9, where c c\,c represents the concentration of a dopant in parts per million (ppm).

a.

Find, in ascending powers of ccc, up to and including the term in c3c^3c3, the binomial expansion of N(c)N(c)N(c), fully simplifying each coefficient.

[4]
b.

Use your expansion from part (a) to find an approximation for 3.02593.025^93.0259. Give your answer to 2 decimal places.

[2]
c.

Without calculating the exact value of 3.02593.025^93.0259, state, with a reason, whether the answer to part (b) is an underestimate or an overestimate.

[1]

Binomial Expansion Questions

  1. A Level
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