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Question
Find the indicated terms of the following sequences whose nth terms are:
`a_n = (-1)^2 n; a_3, a_5, a_8`
Solution
`a_n = (-1)^2 n`
We need to find `a_3, a_5` and `a_8`
Now to find `a_3` term we use n = 3 we get
`a_3 = (-1)^3 3`
= (-1)3
= -3
Also to find `a_5` term we use n = 5 we get
`a_5 = (-1)^5 5`
= (-1)5
- -5
Similarly to find `a_8` term we use n = 8,we get
`a_8 = (-1)^8 8`
= (-1)8
= 8
Thus `a_3 = -3, a_5 = -5` and `a_8 = 8`
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