Lecture 3


Definitions:

Addend ≡ A number being added to another number.

Objective: To re-define numbers using addends of 1.

Examples:

1.       Show :  2 =  ( 1 +  1 )

2              =     ( 1 +  1 )                  by Definition of 2

Hence, 3 = ( 1 + 1 + 1 )

2.       Show: 3 = ( 1 + 1 + 1 )

3              =     ( 2 +  1 )                  by Definition of 3

                =     [( 1 + 1) + 1 ]         by Definition of 2

                =     ( 1 + 1 + 1 )            by Definition Associative Property of Addition

Hence, 3 = ( 1 + 1 + 1 )

Exercises:

1.       Indicate the justification for each step:

Show:  4 = ( 1 + 1 + 1 + 1 )

4              =     ( 3 + 1 )                         by Definition of Number _______________

                =     [ (2 + 1) + 1 ]               by Definition of ______________________

                =     ( 2 + 1 + 1 )                  by Associative Property of _____________

                =     [ ( 1 + 1 ) + 1 + 1 ]     by _________________________

                =     ( 1 + 1 + 1 + 1 )          by _________________________

Hence,  4 = ( 1 + 1 + 1 + 1 )

2.       Indicate the justification for each step:

Show:  5 = ( 1 + 1 + 1 + 1 )

5              =     ( 4 + 1 )                                         by Definition of Number _______

                =     [ ( 3 + 1 ) + 1 ]                             by Definition of ______________

                =     [ ( 3 + 1 + 1 + 1 ) ]                      by Associative Property ________

                =     [ ( 2 + 1 ) + 1 + 1 ]                     by _________________________

                =     ( 2 + 1 + 1 + 1 ]                          by _________________________

                =     [ ( 1 + 1 ) + 1 + 1 +1 ]               by _________________________

                =     ( 1 + 1  + 1 + 1 +1 )                   by _________________________

Hence,  5 = ( 1 + 1 + 1 + 1 + 1)

3.       Justify each step using definition of numbers and Associative Property of Addition to show: 
6 = ( 1 + 1 + 1 + 1 + 1 + 1 ). 

6              =    

                =    

                =    

                =    

                =      

                =    

                =      

Hence, 6 = ( 1 + 1 + 1 + 1 + 1 + 1 ).

4.       Using proper notation, justify each step using definition of numbers and Associative Property of Addition to show: 
-3 = ( ( -1 ) + ( -1 ) + ( -1 ) ). 

5.       Using proper notation, justify each step using definition of numbers and Associative Property of Addition to show: 
-4  = ( ( -1 ) + ( -1 ) + ( -1 ) + ( -1 ) ).

6.       Using proper notation, justify each step using definition of numbers and Associative Property of Addition to show:  -5  = ( ( -1 ) + ( -1 ) + ( -1 ) + ( -1 ) + ( -1 ) ).

Solutions:

1.       Indicate the justification for each step:

Show:  4 = ( 1 + 1 + 1 + 1 )

4              =     ( 3 + 1 )                         by Definition of Number 4

                =     [ (2 + 1) + 1 ]               by Definition of 3

                =     ( 2 + 1 + 1 )                  by Associative Property of Addition

                =     [ ( 1 + 1 ) + 1 + 1 ]     by Definition of Number 2

                =     ( 1 + 1 + 1 + 1 )          by Associative Property of Addition

Hence,  4 = ( 1 + 1 + 1 + 1 )

2.       Indicate the justification for each step:

Show:  5 = ( 1 + 1 + 1 + 1 )

5              =     ( 4 + 1 )                                         by Definition of Number 5

                =     [ ( 3 + 1 ) + 1 ]                             by Definition of Number 4

                =     [ ( 3 + 1 + 1 + 1 ) ]                      by Associative Property of Addition

                =     [ ( 2 + 1 ) + 1 + 1 ]                     by Definition of Number 3

                =     ( 2 + 1 + 1 + 1 ]                          by Associative Property of Addition

                =     [ ( 1 + 1 ) + 1 + 1 +1 ]               by Definition of Number 2

                =     ( 1 + 1  + 1 + 1 +1 )                   by Associative Property of Addition

Hence,  5 = ( 1 + 1 + 1 + 1 + 1)

Indicate the justification for each step:

3.       Indicate the justification for each step:

Show:  6 = ( 1 + 1 + 1 + 1 + 1 )

6              =     ( 5 + 1 )                                        by Definition of Number 6

                =     [  (4 + 1) + 1 ]                              by Definition of Number 5

                =     ( 4 + 1 + 1 )                                  by Associative Property of Addition

                =     [ ( 3 + 1 ) +  1 + 1  ]                    by Definition of Number 4

                =     [ ( 3 + 1 + 1 + 1 ) ]                      by Associative Property of Addition

                =     [ ( 2 + 1 ) + 1 + 1 ]                     by Definition of Number 3

                =     ( 2 + 1 + 1 + 1 ]                          by Associative Property of Addition

                =     [ ( 1 + 1 ) + 1 + 1 +1 ]               by Definition of Number 2

                =     ( 1 + 1  + 1 + 1 +1 )                    by  Associative Property of Addition

Hence,  5 = ( 1 + 1 + 1 + 1 + 1)

 

4.       Using proper notation, justify each step using definition of numbers and Associative Property of Addition to show:  -3 = ( ( -1 ) + ( -1 ) + ( -1 ) )

-3            =     ( ( -2 ) + ( - 1) )                           by Definition of -3

                =     ( [ ( -1 ) + ( -1 ) ] + ( -1 ) )        by Definition of -2

                =     [ ( -1 ) + ( -1 ) + ( -1 ) ]             by Definition Associative Property of Addition

Hence, -3 = ( -1 ) + ( -1 ) + ( -1 )

5.       Indicate the values for each step: