quadratic2 <- function ( a, b, c )

#*****************************************************************************80
#
## quadratic2 computes the roots of a quadratic equation ax^2+bx+c=0.
#
#  Licensing:
#
#    Copyright 2016 James P. Howard, II
#
#    The computer code and data files on this web page are distributed under
#    https://opensource.org/licenses/BSD-2-Clause, the BSD-2-Clause license.
#
#  Modified:
#
#    07 February 2020
#
#  Author:
#
#    Original R version by James Howard.
#    Modifications by John Burkardt.
#
#  Reference:
#
#    James Howard,
#    Computational Methods for Numerical Analysis with R,
#    CRC Press, 2017
#    ISBN13: 978-1-4987-2363-3.
#
#  Input:
#
#    real A, B, C: the coefficients.
#
#  Output:
#
#    real X1, X2: the roots.
{
  t1 <- sqrt ( b^2 - 4.0 * a * c )
  t2 <- 2.0 * c
  x1 <- t2 / ( - b + t1 )
  x2 <- t2 / ( - b - t1 )

  return ( c ( x1, x2 ) )
}