Click here to purchase the entire book in PDF format. Identity Laws These are laws that are pretty obvious, but sometimes they help out. The corresponding laws in normal math are x + 0 = x and x * 1 = x. $$(a + jb) + 0 = (a + jb)$$ (2.39) and $$(a + jb) * 1 = (a + jb)$$ (2.40)