Intro to Logic

This symbol, ∧, means?

• and
• or 
• not 
• implies

This symbol, ∨, means?

• and
• or
• not
• implies

This symbol, ↔, means?

• and
• or 
• if and only if
• implies

Let p represent: Brent works this summer.

Let q represent: Brent takes a vacation.

What is the symbolic representation of this statement?

Therefore, Brent does not work this summer.

• ~p

• ~q

• p v q

• ~q v p

Let V represent Vehicles. Let M represent motorized vehicles, and let A represent automobiles.
Which is not a valid conclusion?

• Not all motorized vehicles are automobiles.
• Not all automobiles are motorized vehicles
• Some motorized vehicles are not automobiles.
• Automobiles are motorized vehicles.

If Anna buys a dress, then she will go to the dance.

Anna bought a dress.

Therefore, she went to the dance.

Is this a valid argument?

• no because it is not logical

• no, even though it is logical all of the statements are not true.

• yes, it is a valid argument

• yes it is valid but not true statements.

*

• All Squares are Quadrilaterals
• All Squares are Rectangles
• All Rectangles are Quadrilaterals
• Some Trapezoids are Rectangles

which of the following completes the statement to form a valid conclusion?

If it is snowing heavily, then school will be canceled.

If school is canceled, the big test will not be given today.

It is snowing heavily, therefore

• look out for the snowplows while driving to school.

• the big test will not be given today.

• the roads will be hard to drive on.

• you should call the school to see if school is canceled.

If it rains on my bike, then it will get rusty.

If it gets rusty, then I can't ride it anymore.

What would be a logical conclusion?

• If it rains on my bike, then I can ride it.

• If it gets rusty, then I can't ride it.

• If it rains on my bike, then I can't ride it anymore.

• None of the above

(1) If a figure is a square, then it is a polygon.

(2) All squares are rectangles..

(3) ???????

What statement belongs in line 3 to make a logically valid conclusion?

• Therefore a square is a polygon.

• A circle is a polygon

• Therefore, a rectangle is a polygon

• invalid; nothing belongs in line 3