If `9t h`term of anA.P. is zero, prove that its `29 t h`term isdouble – InterviewSolution

InterviewSolution

1.	If `9t h`term of anA.P. is zero, prove that its `29 t h`term isdouble the `19 t h`term.
Answer» `T_(9)=0Rightarrow a+8d Rightarrow a=-8d ` ` T_(19)=a+8d =-8d+18d =10d and T_(29) =a+28d =-8d +28d =-8d +28d =20d` `T_(29) = 2xx T_(19)`

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