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The numerically greatest term in the expansion (2x-3y)¹² when x=1 and y= 5/2 is |
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Answer» Given: (2X-3y)¹² , x=1 and y= 5/2 To find: The numerically GREATEST term in the expansion (2x-3y)¹² when x=1 and y= 5/2 is Solution: From given, we have, (2x-3y)¹², x=1 and y= 5/2 we USE the formula, P = [ (n + 1) |x| ] / [|x| + 1] to find the numerically greatest term. so we have, (2x-3y)¹² = (2x)¹²(1 - 3y/2x)¹² Thus we GET, |x| = (3/2) (y/x) substituting the values of x and y, we get, |x| = (3/2) (5/2) = 15/4 Now consider, P = [ (n + 1)|x| ] / [|x| + 1] P = [ (12 + 1) (15/4)] / [15/4 + 1] P = [ (13) (15/4)] / [19/4] P = 195/19 = 10.26 Thus 10.26 ≈ 11, 11TH term is the numerically greatest term in the expansion (2x-3y)¹² when x=1 and y= 5/2. |
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