Ok, so I'm doing some logic review on my own. It's been awhile since I've done derivations, so I'm a little rusty. I'm just trying to use SD rules and not SD+. I'd appreciate any help you all can offer. Thanks in advance.(adsbygoogle = window.adsbygoogle || []).push({});

Derive: (G&H)->J

1. E->(F->G) assum.

2. H->(G->I) assump

3. (F->I)->(H->J) assump

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4. |E assumption

5. | |G&H assumption

6. | |H 5 &E

7. | |G->I 6,2 ->E

8. | |F->G 4,1 ->E

9. | | |F asummp

10. | | |G 8,9 ->E

11. | | |I 7,10 ->E

12 | | F->I 9-11 ->I

13. | | H->J 3, 12 ->E

14. | | J 6, 13 ->E

15. | (G&H)->J 5-14 ->I

This is where I get stuck. I do get #15 out of the subderivation of E? Or am I going about this all wrong? Can you even derive this thing?

Thanks

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# Help with an SD derivation

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