the denominator of a fraction is one more than twice the numerator if the sum of fraction and its reciprocal is 2 16/21 find the fraction
Answers
Answer:
Step-by-step explanation:
Let the numerator of the fraction be x. Then the denominator of the fraction is 2x + 1. The required fraction is .
21(5x 2 + 4x + 1) = 58(2x 2 + x)
105x 2 + 84x + 21 = 116x 2 + 58x
11x 2 - 26x - 21 = 0
11x 2 - 33x + 7x - 21 = 0
11x(x – 3) + 7(x – 3) = 0 (11x + 7)(x – 3) = 0 11x + 7 = 0 or x – 3 = 0 The required fraction is
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Answer:
Step-by-step explanation:
Correct Question :-
The denominator of a fraction is one more than twice the numerator. If the sum of the fraction and its reciprocal is 2(16/21), find the fraction.
Answer :-
Solution :-
Let the numerator be x.
And the fraction = x/2x + 1
According to the Question,
Again x/2x + 1 + 2x + 1/x = 58/21
⇒ x² + (2x - 1)²/x(2x + 1) = 58/21
⇒ 5x² + 4x + 1/2x² + x = 58/21
⇒ 21(5x² + 4x + 1) = 58(2x² + x)
⇒ 105x² + 84x + 21 = 116x² + 58x
⇒ 11x² + 26x - 21 = 0
⇒ 11x² + 33x - 7x - 21 = 0
⇒ 11x(x + 3) + 7(x + 3) = 0
⇒ x = 3, - 7/11 (x can't be negative)
Hence, the required fraction is 3/7.