Completing The Square

In elementary algebra, completing the square is a technique for converting a quadratic polynomial of the form

to the form

In this context, "constant" means not depending on x. The expression inside the parenthesis is of the form (x − constant). Thus one converts ax2 + bx + c to

and one must find h and k.

Completing the square is used in

  • solving quadratic equations,
  • graphing quadratic functions,
  • evaluating integrals in calculus, such as Gaussian integrals with a linear term in the exponent
  • finding Laplace transforms.

In mathematics, completing the square is considered a basic algebraic operation, and is often applied without remark in any computation involving quadratic polynomials.

Read more about Completing The Square:  Relation To The Graph, Solving Quadratic Equations, Geometric Perspective, A Variation On The Technique

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