# Geometry (Logic)

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Which argument is not valid?

1.) Given: a→b
a
Conclusion: b

2.) Given: a˅b
~b
Conclusion: ~a

3.) Given: a→b
~b
Conclusion: ~a

4.) Given: a→b
b→~c
Conclusion: a→~c

• Geometry (Logic) -

#2 is not an argument, since there is no implication.

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