Buktikan menggunakan sifat bilangan Riil.
Bantu
Jika z dan a unsur di R sehingga z + a = a, maka z = 0, ….
PIKIREN-(39$9%;4($939(3+$+++4%8%8+;3+$+8$8382(+$:4:%-39282+:$=839393939939993939393939939393939393939393939393939393939393939393939393939393939393939393993939393939393933333339939339393993993930393933993