@Test public void testMultiply() { MyDouble a = new MyDouble(1); MyDouble b = new MyDouble(2); MyDouble c = new MyDouble(3); QuadraticEquation TestOneQuad = new QuadraticEquation(a, b, c); QuadraticEquation TestTwoQuad = new QuadraticEquation(a, b, c); QuadraticEquation MultiQuadNull = TestOneQuad.limitedMultiply(TestTwoQuad); assertEquals(null, MultiQuadNull); QuadraticEquation TestThreeQuad = new QuadraticEquation(c); QuadraticEquation MultiQuad = TestOneQuad.limitedMultiply(TestThreeQuad); QuadraticEquation MultiTest = new QuadraticEquation(a.multiply(c), b.multiply(c), c.multiply(c)); assertTrue(MultiQuad.equals(MultiTest)); }