Modifers

1.

Write a new method called negate that reverses the sign of a rational number. It will look a lot like the conjugate method of the Complex class, except that it should negate the numerator instead of the imaginary part.

2.

Add lines to main to test the new method.

3.

Write a method called invert that inverts the number by swapping the numerator and denominator. This method is also a modifier, and should also return void. Add lines to main to test the new method.