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2 votes
2 votes
20. If a+


(1)/(a)
=

√(29)
, find the values of 2a-

(2)/(a)


User Ranjeet
by
2.9k points

1 Answer

12 votes
12 votes

Answer:

  • 10

Explanation:

Given:

  • a + 1/a =
    √(29)

Square both sides:

  • a² + 1/a² + 2 = 29
  • a² + 1/a² = 27

Now, square the 2a - 2/a:

  • 2(a - 1/a)² =
  • 4(a² + 1/a² - 2) =
  • 4(27 - 2) = Substitute 27
  • 4*25

Find the square root:


  • √(4*25) = 10
User Sybren
by
2.4k points