Arithmetic - Number System

Question 1

natural numbers

Answer 1

counting numbers

N=1,2,3,…∞

Question 2

whole numbers

Answer 2

counting numbers & 0

W=0,1,2,3,…∞

Question 3

negative numbers

Answer 3

number less than zero

Question 4

integer

Answer 4

a whole number (not a fractional number) | can be positive, negative, or zero
I=…,-3,-2,-1,0,1,2,3,…

Question 5

even number

Answer 5

a number is even if it is divisible by 2 and remainder is zero

Question 6

odd number

Answer 6

a number is odd if it is not divisible by 2 and remainder is 1

Question 7

prime number

Answer 7

a positive integer with only two factors, 1 and itself

Question 8

prime numbers between 1 and 200

Answer 8

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199

Question 9

composite numbers

Answer 9

a positive integer which is not prime (i.e., has factors other than one and itself)

Question 10

rational numbers

Answer 10

a number which can be expressed in the form p/q, where p and q are integers and q≠0
Example: 3/4, 7/1

Question 11

irrational numbers

Answer 11

a real number that cannot be written as a simple fraction

Example: π = 3.1415…. as a fraction it could only be written as an approximation 22/7

Question 12

imaginary number

Answer 12

i=√-1 useful for calculating the square roots of negative numbers

Question 13

complex number

Answer 13

a combination of real and imaginary numbers

Example: -2+πi, 2+3i