1. Outline a proof of the following proposition. Proposition: For all real numbers a and b. if V a2 + {)2 = a + b then a = 0 or b = 0. 2. Outline a proof of the following proposition. Proposition: Let n be an integer. If n E 1(mod 4) or n E 3(I110Ci 4) then n2 E (mod 4)