MATH 245 Exam 2

converse

If P, then Q," the _____ is "If Q, then P"

Inverse

If P, then Q, the ____ is "If not P, then not Q."

contrapositive

If P, then Q, the ____ is "If not Q, then not P."

odd

if n=2k+1 for some integer k.

even

if n=2kfor some integer k.

AUB the union

A∪B={x∣x∈A OR x∈B}

Cartesian

ormula:

𝐴×𝐵={(𝑎,𝑏)∶ 𝑎∈𝐴 and 𝑏∈𝐵} For all sets A and B, every element of AXB is an ordered pair of the form (x,y), where x is a subset and y is a subset.

Intersection

A∩B={x∣x∈A AND x∈B}

Complement:

A^c

{x∣x∉A}

Rational Number

x=b/a​, a,b∈Z,  b is not equal to 0