Q7 of 83 Page 90

Find a number greater than 1 such that the sum of the number and its reciprocal is 2 .

Let the no.be x.





⇒ 15x2 + 15 = 34x


⇒ 15x2 – 34x + 15 = 0


⇒ 15x2 – (9 + 25)x + 15 = 0


⇒ 15x2 – 9x – 25x + 15 = 0


⇒ 3x(5x – 3) – 5(5x – 3) = 0


⇒ (3x – 5) = 0 or (5x – 3 = 0)]]


or


and


∴ The required no is


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