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The first and the second terms of an AP are 5 2 and 23 12 respectively. If n^ th terms is the largest negative term, what is the value of n ?

Options

  1. A5
  2. B6
  3. C7
  4. Dn cannot be determined

Correct answer

B. 6

Step-by-step solution

a= 5 2 a+d= 23 12 d= 23 12 - 5 2 = -7 12 The largest negative term will be the first negative term as it is decreasing A P . i.e. T n 0 a+(n-1) d 0 5 2 +(n-1) (- 7 12 ) 030-7(n-1) 0 30-7 n+7 07 n 37 n 37 7 For integer value, n=6 .

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