Find the sum of the products of the corr | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

Question:

Find the sum of the products of the corresponding terms of the sequences 2, 4, 8, 16, 32 and 128, 32, 8, 2, $1 half$ .

Answer:

Required sum = 2 × 128 + 4 × 32 + 8 × 8 + 16 × 2 + 32 × $1 half$

$equals space 64 space open square brackets 4 space plus space 2 space plus space 1 space plus 1 half space plus space 1 over 2 squared close square brackets$

Here, 4, 2, 1, $1 half comma space 1 over 2 squared$ is a G.P.

First term, a = 4

Common ratio, r = $1 half$

It is known that,

$S subscript n space equals space fraction numerator a space open parentheses 1 minus r to the power of n close parentheses over denominator 1 minus r end fraction therefore space S subscript 5 space equals space fraction numerator 4 open square brackets 1 minus open parentheses begin display style 1 half end style close parentheses to the power of 5 close square brackets over denominator 1 minus begin display style 1 half end style end fraction equals fraction numerator 4 open square brackets 1 minus begin display style 1 over 32 end style close square brackets over denominator begin display style 1 half end style end fraction equals fraction numerator 8 open parentheses 32 minus 1 close parentheses over denominator 32 end fraction equals 31 over 4 therefore space R e q u i r e d space s u m space equals space 64 space open parentheses 31 over 4 close parentheses space equals space open parentheses 16 close parentheses open parentheses 31 close parentheses space equals 496$

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Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

Read the question carefully and focus on the core concept being asked.
Reference examples and data from the chapter when answering questions about Sequence and Series.
Review previous year question papers to get an idea of how such questions may be framed in exams.
Practice answering questions within the time limit to improve your speed and accuracy.
Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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nagendrababu
2017-11-22 14:43:46

awesom

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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 19: Find the sum of the products of the corresponding terms of the sequences 2, 4, 8, 16, 32 and 128, 32....

Find the sum of the products of the corr | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

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