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AP EAMCET202120 Aug 2021Evening ShiftMathematicsQuadratic EquationActual

For a ≠ b , if the equation x 2 + a x + b = 0 and x 2 + b x + a = 0 have a common root, then the value of a + b =

Options

  1. A- 1
  2. B0
  3. C1
  4. D2

Correct answer

A. - 1

Step-by-step solution

Given: x 2 + a x + b = 0   &   x 2 + b x + a = 0 Here, we can see that for x = 1 both the equations are giving same expression, which is, 1 + a + b = 0 ⇒ a + b = - 1

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