求出下列每对数在数轴上对应点之间的距离(1)3与-2.2(2)4.75与2.25(3)-4与-4.5(4)-3又2/3与+2又1/3
问题描述:
求出下列每对数在数轴上对应点之间的距离
(1)3与-2.2
(2)4.75与2.25
(3)-4与-4.5
(4)-3又2/3与+2又1/3
答
由两点距离为丨a-b丨得:
(1)丨3-2.2丨=0.8
(2)丨4.75-2.25丨=2.5
(3)丨-4-(-4.5)丨=0.5
(4)丨-3又2/3-2又1/3丨=1又1/3
答
解(1)/3-(-2.2)/=5.2
(2)/4.75-2.25/=2.5
(3)/-4-(-4.5)/=0.5
(4)/-3又2/3-(2又1/3)/
=/-8/3-7/3/
=15/3
=5
答
(1)3与-2.2
=|3-(-2.2)|
=|3+2.2|
=5.2
(2)4.75与2.25
|4.75-2.25|
=|25.5|
=2.5
(3)-4与-4.5
|(-4)-(-4.5)|
=|-4+4.5|
=0.5
(4)-3又2/3与+2又1/3
|(-3又2/3)-(+2又1/3)|
=|-6|
=6
答
(1)5.2
(2)2.5
(3)0.5
(4)6