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Consider an infinite geometric series with first term a and common ratio r . If its sum is 4 and the second term is 3 4 , then:

Options

  1. Aa= 4 7 , r= 3 7
  2. Ba=2, r= 3 8
  3. Ca= 3 2 , r= 1 2
  4. Da=3, r= 1 4

Correct answer

D. a=3, r= 1 4

Step-by-step solution

Since, sum =4 and second term = 3 4 a 1-r =4 , and a r= 3 4 a 1- 3 4 a =4 (a-1)(a-3)=0 a=1 or a=3 array l a 1- 3 4 a =4 (a-1)(a-3)=0 a=1 or a=3 array

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