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No Stupid Questions@lemmy.world · 6 months ago

Is "If A then B" equal to "B if and only if A"?

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Is "If A then B" equal to "B if and only if A"?

Lafari@lemmy.world to

No Stupid Questions@lemmy.world · 6 months ago

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zenharbinger@lemmy.world
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6 months ago
B can still be true when a is false. iff means that b can only be true when a is true.

Also, the equivalent statement is.

vehicle if and only if car.

not

car only if vehicle

since a truck is a vehicle, the statement is false.

Somewhat wrong above:

A B a iff b

T T T

T F F

F T F

F F T

look online for truth tables.

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