Please do work as shown in the example.

Example:

l Prove that l+2+3 = 6 1 + 2 + 3 = 6 3 + 3 = 6 ZC 6 = 6 T This is complete and utter nonsense and proves nothing whatsoever because what is to be proved has been assumed in the first step. Furthermore, one can establish the formula T from the empty set of premises. This abomination is common and will be severely penalized. FC L8 = 1+2+3 = 3+3 = 6 = RS is acceptable. FC R5 = 6 = 3+3 = 1+2+3 = LS is acceptable. LS R5 = 1 + 2 + 3 = _;_,__.__' is acceptable. FC L5 = 6 = R5 Due by2359 hours on 20220920 163 Exam 1A 5 (1c) Circle correct choices from among Y, N, Proof, and Witness and provide below a proof or witness as the case may be: 1 (i) ZO ME NB XA x - y=x Y N Pf W Why? 1 (ii) 3x E N (x - y=-y) Y N PF W Why? 1 (iii) NB XA By E Z (x + y = 0) Y N Pf W Why? 1 (iv) 3x EZ ( xy 50) Y N Pf) W Why? 1 (v) 3x EZ By E Z ( x ty+xy = 1) Y N Pf W Why? You may discuss with anyone 107Due by2359 hours on 20220920 163 Exam 1A 6 (2a) Answer the following: 1 ( 1) Y N Pf W Why ? 1 (ii) Y N Pf W Why? 1 (iii) 15 0,(1) Y N Pf W Why? 1 (iv) Y N Pf W Why? 1 ( v ) Y N Pf W Why? 1 (vi) Y N Pf W Why? 109 You may discuss with anyone