Prerequisite –
Taylor theorem and Taylor series
We know that formula for expansion of Taylor series is written as:
Now if we put a=0 in this formula we will get the formula for expansion of Maclaurin series. T
hus Maclaurin series expansion can be given by the formula –
Maclaurin series expansion of some elementary functions :
-
Exponential function :
Differentiating n times,
So we get
Thus
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f(x) = cos x
…..
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f(x) = sin x
-
f(x) = (ax + b)^m
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f(x) = ln(1+x)
-
f(x) = ln(1-x)
Example-1:
Find the first seven terms of f(x) = ln(sec x).
Explanation :
Differentiating w.r.t. x,
Thus we get the Maclaurin series as –
Example-2:
Evaluate Maclaurin series for tan x.
Explanation :
Thus we get Maclaurin series as –