MMW 3-7

Σ

the sum of

∃

there exists

∈

element of

∀

for every

≅

approximately equal to

∞

infinity

∴

therefore

+

sum, total, increased by, more than

-

minus, less than, decreased by, reduced by, difference

×

times, product, doubled, squared, cubed

÷

ratio, divided by, quotient, per, average

=

equals, is, results in, is equivalent to

∧ conjunction (and)

T T = T
T F = F
F T = F
F F = F

v disjunction (or)

T T = T
T F= T
F T=T
F F=F

conditional (if-then) (p→q)

TT=T
TF=F
FT=T
FF=T

biconditional (if and only if) (←→)

TT=T
TF=F
FT=F
FF=T

N

Natural Numbers

Z

Integers

Q

rational numbers

Q′

Irrational numbers

R

Real numbers