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If 7 times 7th term of a AP is equal to 11 times the 11th term, thenterm.findthe18h |
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Answer» 7th term = (a+6d) 11th term = (a+10d)(a+6d)7 since 7th term of the ap is 7 times and the same for 11th term(a+6d)7=(A+10d)11 (given)7a + 42d =11a +110d (on solving)7a - 11a = 110d - 42d-4a = -68da= -17d we know 18th term = (a+17d)................................. (i)now we substitute the value of a in (i)which emplies, -17d + 17d = 0hence prove.. |
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