Question

Construct derivations in SD+ that establish the following:
The following argument is valid:

(B É C) v (B É ~A)
E & ~C		\ ~(A & B)

Symbol meaning:
v is disjunction (or)
& is conjunction (and)
É is implication (if, then)
~ is a negative (not)
Three dots means therefore

Answer 1

Construct an annotated derivation for the augment

So far I have for this derivation

1. Show B É C Assertion

2. Show B É ~ A assertion

3. ~ A Assumption ( conditional derivation )

4. (B É C) v ( B É ~A) premise 1

5. E & ~C premise 2

6. ~C premise 3

My next bus going to be using ~A to get B É ~A from ( B É C) with modules Tollens ponens. I m trying to aim for a conditional derivation by getting C itself to then achieve a Conditional Dysjunction .

1. Construct an annotated derivation for the argument

2. ( B É C) v ( B É ~A) and E & ~C

For this one i have :

1. Show E & ~ C

2. Show Assertion of B É C

3. C assumption

4. ~ C negation

Hence ( B É C ) v ( B É ~ A)

E & ~ C

Somehow i got negation of what the conditional consequent and i don't know how to fix it so that i can actually get the consequent without a negation .