2. If the sum of the first 12 terms of a geometric series is 8190 and the common ratio is 2. Find the first term and the 20th term

the first term is 2 and the 20th term is 1048576 .

Step-by-step explanation:

Here we have , If the sum of the first 12 terms of a geometric series is 8190 and the common ratio is 2. We need to Find the first term and the 20th term. Let's find out:

We know that Sum of a GP is :

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So ,Sum of first 12 terms is :

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Now , nth term of a GP is

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So , 20th term is :

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Therefore , the first term is 2 and the 20th term is 1048576 .