@Test
void find_whenQuarticHasFourRealRoots_thenReturnsCorrectRoots() {

    ImmutableList<Complex> roots = QuarticRootFinder.find(3, 6, -123, -126, 1080);
    ImmutableList<Pair<Double, Double>> expectedRoots = ImmutableList.of(
            Pair.of(5.0, 0.0),
            Pair.of(3.0, 0.0),
            Pair.of(-4.0, 0.0),
            Pair.of(-6.0, 0.0)
    );
    assertEquals(expectedRoots, roots);
}