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JEE Advanced 2008Paper 2
Exam
JEE Advanced
Year
2008
Paper
Paper 2
Subject
Mathematics
Chapter
Sequences and Series

JEE Advanced 2008 · Paper 2 · Mathematics · Sequences and Series

Suppose four distinct positive numbers a_1, a_2, a_3 and a_4 are in...

Suppose four distinct positive numbers a1,a2,a3a_1, a_2, a_3 and a4a_4 are in GP. Let b1=a1b_1=a_1, b2=b1+a2,b3=b2+a3b_2=b_1+a_2, b_3=b_2+a_3 and b4=b3+a4b_4=b_3+a_4. Statement 1 The numbers b1,b2,b3b_1, b_2, b_3 and b4b_4 are neither in AP nor in GP. Statement 2 The numbers b1,b2,b3b_1, b_2, b_3 and b4b_4 are in HP.

Options

  1. AStatement 1 is true, Statement 2 is true, Statement 2 is a correct explanation for Statement 1.
  2. BStatement 1 is true, Statement 2 is true, Statement 2 is not a correct explanation for Statement 1.
  3. CStatement 1 is true, Statement 2 is false.
  4. DStatement 1 is false, Statement 2 is true

Correct answer

C. Statement 1 is true, Statement 2 is false.

Step-by-step solution

Let a1=1,a2=2,a3=4,a4=8a_1=1, a_2=2, a_3=4, a_4=8 \therefore b_1=1, b_2=3, b_3=7, b_4=15 Clearly, b1,b2,b3b_1, b_2, b_3 and b4b_4 are not in HP. Statement 2 is false.
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