Science:Math Exam Resources/Courses/MATH103/April 2015/Question 01 (e) (iii)/Solution 2

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Again, we can find the answer by eliminating the options. The remaining options are and .

At , is equal to 0, however the given series at is equal to 1.

although is equal to 1 at , its Taylor series does not have any odd degree term because its 1st, 3rd, 5th, ... derivative vanish at , so the only option is .