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Find the sum to n terms in the geometric progression 1,-a, a...

Find the sum to n terms in the | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

Question:

Find the sum to n terms in the geometric progression 1,-a, a²,-a³, ... (if a ≠ -1)

Answer:

The given G.P. is 1,-a, a²,-a³, .........

Here, first term = a1 = 1

Common ratio = r = – a

$S subscript n equals fraction numerator a subscript 1 open parentheses 1 minus r to the power of n close parentheses over denominator 1 minus r end fraction s o S subscript n equals fraction numerator 1 open square brackets 1 minus open parentheses minus a close parentheses to the power of n close square brackets over denominator 1 minus open parentheses minus a close parentheses end fraction space equals space fraction numerator open square brackets 1 minus open parentheses minus a close parentheses to the power of n close square brackets over denominator 1 plus a end fraction$

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Welcome to the NCERT Solutions for Class 11 Mathematics - Chapter . This page offers a step-by-step solution to the specific question from Excercise 3 , Question 9: Find the sum to n terms in the geometric progression 1,-a, a2,-a3, ... (if a ≠ -1)....

Find the sum to n terms in the | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

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