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Rewrite the function by completing the square f(x)=x^2+x-30

User AaronJPung
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1 Answer

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Final answer:

Rewritten the function by completing the square, will get f(x) = (x + 1/2)^2 - 121/4.

Step-by-step explanation:

To rewrite the function by completing the square, we need to follow the steps below:

  1. Move the constant term to the other side of the equation:
  2. x^2 + x = 30
  3. Take half of the coefficient of x and square it:
  4. (1/2)^2 = 1/4
  5. Add this value to both sides of the equation:
  6. x^2 + x + 1/4 = 30 + 1/4
  7. Factor the perfect square trinomial on the left side:
  8. (x + 1/2)^2 = 30 + 1/4
  9. Simplify the right side of the equation:
  10. (x + 1/2)^2 = 121/4
  11. Take the square root of both sides:
  12. x + 1/2 = ±√(121/4)
  13. Solve for x:
  14. x = -1/2 ±√(121/4)

Therefore, the rewritten function is f(x) = (x + 1/2)^2 - 121/4.

User Filype
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