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Question
Find the indicated terms in the following sequences whose nth terms are:
an = 5n - 4; a12 and a15
Solution
Here, we are given the nth term for various sequences. We need to find the indicated terms of the A.P.
`a_n = 5n - 4`
We need to find `a_12` and `a_15`
Now to find `a_12` term we use n = 12 we get
`a_12 = 5(12) - 4`
= 60 - 4
= 56
Also to find `a_15` term we use n = 15, we get
`a_15 = 5(15) - 4`
= 75 - 4
= 71
Thus `a_12 = 56` and `a_15 = 71`
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