คำชี้แจง  จงแสดงการหาผลบวกต่อไปนี้บนเส้นจำนวน

1.      4 + 3

        ................................................................................................................................................................

        ดังนั้น 4 + 3 = .........................................................................................................................................

2.      (-4) + (-3)

        ................................................................................................................................................................

        ดังนั้น (-4) + (-3) = .................................................................................................................................

3.      (-3) + (-4)

        ................................................................................................................................................................

        ดังนั้น (-3) + (-4) =..................................................................................................................................

4.      [(-4) + (-3)] + (-2)

        ................................................................................................................................................................

        ดังนั้น [(-4) + (-3)] + (-2) = ....................................................................................................................

5.      (-4) + [(-3) + (-2)]

        ................................................................................................................................................................

        ดังนั้น (-4) + [(-3) + (-2)]........................................................................................................................

คำชี้แจง จงแสดงการหาผลบวกต่อไปนี้บนเส้นจำนวน

1.      (-3) + (-2)

        ................................................................................................................................................................

        ดังนั้น (-3) + (-2) =..................................................................................................................................

2.      (-2) + (-3)

        ................................................................................................................................................................

        ดังนั้น (-2) + (-3) = .................................................................................................................................

        จากข้อ 1 และ 2 พบว่า (-3) + (-2) = (-2) + (-3)

        จำนวนเต็มลบมีสมบัติการสลับที่สำหรับการบวกหรือไม่ .....................................................................

3.      (-5) + (-2) + (-3)

        ................................................................................................................................................................

        ดังนั้น (-5) + (-2) + (-3) = .......................................................................................................................

4.      [(-5) + (-2)] + (-3)

        ................................................................................................................................................................

        ดังนั้น [(-5) + (-2)] + (-3) = ....................................................................................................................

5.      (-5) + [(-2) + (-3)]

        ................................................................................................................................................................

        ดังนั้น (-5) + [(-2) + (-3)] = ....................................................................................................................

        จากข้อ 3, 4 และ 5 พบว่า (-5) + (-2) + (-3) = [(-5) + (-2)] + (-3) = (-5) + [(-2) + (-3)]

        จำนวนเต็มลบมีสมบัติการเปลี่ยนกลุ่มสำหรับการบวกหรือไม่ ........................................................

คำชี้แจง จงหาคำตอบในแต่ละข้อต่อไปนี้

1. จงหาค่า

        1)      (-10) + (-8) = ..........................................       6)      [(-6) + (-1)] + (-3) = ...............................

        2)      (-8) + (-10) = ..........................................       7)      (-200) + (-80) + (-5) = .................…......

        3)      (-6) + (-3) + (-1) = .................…….........          8)      [(-200) + (-80)] + (-5) = ................…....

        4)      [(-6) + (-3)] + (-1) = .....................…….            9)      (-200) + [(-80) + (-5)] = ...................….

        5)      (-6) + [(-3) + (-1)] = ....................……..           10)     [(-200) + (-5)] + (-80) = ...................….

2. จงพิจารณาประโยคต่อไปว่าเป็นจริงหรือไม่

        1) จำนวนเต็มลบมีสมบัติการสลับที่สำหรับการบวกหรือไม่

        2) จำนวนเต็มลบมีสมบัติการเปลี่ยนกลุ่มสำหรับการบวกหรือไม่