#### Please solve the problem below

Use your logic skills to derive the conclusion -(-R&-S) from the following assumptions.

D J L Formula
Lines
Rule
1 -(R∨S)→M A
2 M→(N&O) A
3 -(N&O) A
4)
Lines
• &
• -
• (
• )

## Help!

#### What symbols can I use, and how do I enter them?

The following is a list of characters that can be used

• ✰ Any alphabetical character from A all the way to Z
• ✰ The conditional operator ( → ) can be inserted if you press the shift key and the > key at the same time
• ✰ The bi-conditional operator ( ↔ ) can be inserted if you press the shift key and the < key at the same time
• ✰ The disjunction operator ( ∨ ) can be inserted if you press the shift key and the v key at the same time
• ✰ The conjunction operator ( & ) can be inserted as you normally would type an ampersand
• ✰ The negation operator ( - ) can be inserted as you normally would type a dash
• ✰ Opening ( and closing ) parentheses can be inserted as you normally would type them
• ✰ Spaces!

The following list, though not exhaustive, cannot be entered

• ☹ Numerals ie 1234567890
• ☹ Punctuation like , . or even ?
• ☹ Brackets like { or [
• ☹ Probably some other stuff