Multiplication is shorthand for repeated addition, for example 5 × 4 is the same as 5 + 5 + 5 + 5 or 4 + 4 + 4 + 4 + 4. Repeatedly adding a positive number to itself will result in a positive number.
A rational number is not. But the set of ALL rational numbers is.
Closure with respect to addition and multiplication. Cummutative, Associative properties of addition and of multiplication. Distributive property of multiplication over addition.
No. The set of rational numbers is closed under addition (and multiplication).
Rules of operators additon and multiplication (+) + (+) = + (+) + (-) OR (-)+(+)= sign of bigger number (-) + (-) = -(operation is addition but sign is -) (+) * (+) = + (-) * (-) = + (+) * (-) OR (-)*(+)= -
In multiplication/division the answer will always be negative and in addition/subtract the answerwill have the sign of the larger number
In addition, it depends on which is larger. In multiplication, a negative times a positive is alway negative.
Is { 0, 20 } closed under multiplication
The opposite of a number depends on what the relevant operation is. For addition or multiplication - the two common operators - the answer to the question depends on what the first number is.
No. A number cannot be closed under addition: only a set can be closed. The set of rational numbers is closed under addition.
The distributive property of multiplication over addition.
Multiplying positive numbers will result in a positive number.