A set is uncountable
if there is no one-to-one correspondence between the elements of
the set and the natural numbers. The set of real numbers is uncountable.
of two given sets A & B is the set of all elements that are
belonging to either A or B or both. For example,let A = (-1, 5)
and B = (0, 6) be two open intervals of real numbers, then the union
of A and B is ,
which is the set of all real numbers between -1 and 6.
Being the only
value satisfying some condition.
for the Fundamental Theorem of Arithmetic and it states that
any counting number is either a prime number or a composite number
that can be factored as a product of prime numbers in a unique way,
except for the order in which they are written.
The first position
in a place-value counting system, representing a single-digit number.
A letter whose value(s) is to be determined by solving an equation.