plz answer my ques dear friends....
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it's option d may be
hope it will help you mark me as brainliest
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Answer:
1) S1: = 1 + 3 + 5 + 7 + ---- + (2n-1) [nth term; a + (n-1)d;
nth term = 1 + (n-1)2 = (2n-1)]
2) Sum to n terms of an AP: (n/2){1st term + Last term};
S1 = (n/2)*(1 + 2n -1) = (n^2)
3) S2 = 1 + 5 + 9 + 13 + ---- + (2n-3)
S2 = {(n/2)/2}*(1 + 2n -3) = (n/4)*(2n-2) = (n)(n-1)/2
So, S1/S2 = (n^2)/{(n)(n-1)/2} = 2n/(n-1)
Now let us consider, the number of terms in S1 are odd;
Last term here = 1 + {(n+1)/2 - 1}4 = 1 + 2n + 2 - 4 = 2n - 1
S2 = {(n+1)/2)/2}*(1 + 2n -1) = (n)*(n+1)/2
So, in this case the ratio S1/S2 = 2n/(n+1)
Hope This Helps :)
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