If 19^th term of a non-zero A.P. is zero, then ifn ( 49^th term) :n ( 29^th . term ) is

(c) : Let a be the first term and d be the common difference.n nGiven, a_19=a+18 d=0 => a=-18 dnnTherefore (a+48 d / a+28 d)=(-18 d+48 d / -18 d+28 d)=(30 d / 10 d)=(3 / 1)n

If 19^{{th}{~}} term of a non-zero A.P. is zero, then i... | Sequence & Series (Mathematics)

a

be the first term and

d

be the common difference.\n \nGiven,

a_{19}=a+18 d=0 \Rightarrow a=-18 d

\n\therefore \frac{a+48 d}{a+28 d}=\frac{-18 d+48 d}{-18 d+28 d}=\frac{30 d}{10 d}=\frac{3}{1}\n

Explanation

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