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AP EAMCET2015MathematicsQuadratic Equation

If the harmonic mean of the roots 2 x^2-b x+(8-2 d )=0 is 4 , then the value of b is

Options

  1. A2
  2. B3
  3. C4- 5
  4. D4+ 5

Correct answer

C. 4- 5

Step-by-step solution

Given equation 2 x^2-b x+(8-2 5 )=0 Let the roots of the given equation are and . Sum of roots, + = -b a =- ( -b 2 )= b 2 and product of roots, = c a = 8-2 5 2 Now, as given in the question aligned & 2 + =4 2 ( 8-2 5 2 ) b 2 =4 & 2 ( 8-2 5 2 )=b b=4- 5 aligned

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