Logic: Conjunctions and Disjunctions
In logic, two statements can be combined to form a
compound statement using and, or a compound statement
using or.
It is raining andI am leaving. It is raining orI am leaving.
A compound statement using andis called a conjunction.
It is true only when bothoriginal statements are true.
A right angle measures 90 and a straight angle measures 180. True
A compound statement using oris called a disjunction.
It is true when bothof the original statements are true
or when oneof the original statements is true.
A rhombus has 4 sides or a square has 4 sides. True
Eleven is a prime number or eleven is a composite number. True
A rectangle is a space figure or a prism is a plane figure. False
Write a conjunction statement and a disjunction statement
for each exercise. Then tell whether each is TrueorFalse.
0 1. A robin is a bird. 0 2. A boat can float.
- A dime is worth exactly 5¢. 01. A plane can fly.
0 3. Eighteen is a prime number. 0 4. 144 12 12
- One is a composite number. 01. 56 5 280
0 5. 2400 80 2320 0 6. (173) 4 5
- 75 69 6 01. 147 58 83
True True
True
True
False
True
False
False
8206-2_491 3/23/06 2:48 AM Page 491