This proof shows that an ADD instruction that stores the sum in memory cell #2 does not affect memory cell #1. It uses ADD Instruction Property 2 and performs some basic algebra to compute the value of memory cell #1 at time 1.

Note that src1 and src2 are left as variables because these values do not affect memory cell #1. In other words, this property is true regardless of the value of src1 and src2.

For reference, here is the simulator. We cannot use variable values so src1 is set to 1 and src2 is 2:

Quiz (1 point)

• not (1 = 2)
• 0 + a = a

• if the following are true:

  • instruction #i is add dst=d src1=s1 src2=s2
  • the PC at time t = i
  • not (other = d)

  then value of cell other at time (t + 1) = value of cell other at time t

• if 0 + 1 = 1, then value of cell 1 at time (0 + 1) = value of cell 1 at time 1

• if the following are true:

  • a = b
  • a = c
  • b = d

  then c = d

Please write your proof in the table below. Each row should contain one claim. The last claim is the statement that you are trying to prove.

Step	Claim	Reason (optional)	Error Message (if any)
1
2
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