根号20

1,1

2,1.41

3,1.732

4,2

5,2.236

6,2.44948974278318

7,2.64575131106459

8,2.82842712474619

9,3

10,3.838

11,3.34

12,3.4641

13,3.69

14,3.744

15,3.87298334620742

16,4

17,4.1231

18,4.24264068711928

19,4.35889894354067

20,4.472

21,4.58257569495584

22,4.69

23,4.79583152331272

24,4.89897948556636

25,5

26,5.78

27,5.663

28,5.2915

29,5.3851648071345

30,5.47722557505166

31,5.56776436283002

32,5.65685424949238

33,5.74456264653803

34,5.83

35,5.916

36,6

37,6.22

38,6.898

39,6.2449979983984

40,6.32455532033676

41,6.45

42,6.48

43,6.557438524302

44,6.6332495807108

45,6.77

46,6.78232998312527

47,6.85565460040104

48,6.9282

49,7

50,7.48

51,7.285

52,7.2111

53,7.28

54,7.34846922834953

55,7.466

56,7.48331477354788

57,7.54983443527075

58,7.691

59,7.681

60,7.74596669241483

61,7.81

62,7.874

63,7.93725393319377

64,8

65,8.55

66,8.124

67,8.245

68,8.24621125123532

69,8.37

70,8.3666

71,8.426

72,8.48528137423857

73,8.544

74,8.63

75,8.66

76,8.735

77,8.77496438739212

78,8.835

79,8.888

80,8.94427190999916

81,9

82,9.42

83,9.11

84,9.168

85,9.289

86,9.2736184954957

87,9.32737905308882

88,9.38

89,9.4339811320566

90,9.48683298050514

91,9.53939201416946

92,9.594

93,9.64365076099295

94,9.69535971483266

95,9.74679434480896

96,9.79795897113271

97,9.8488578017961

98,9.89949493661167

99,9.9498743710662

100,10

这不用背,把根式里能表示某个数的平方的提出来,不能提的放根式里不动.

例:√20=2√5

20=4*54是2的平方,就提2出来,5在根式里不动.

数学要灵活运用,找到规律就行了!

√1=1

√2=√2

√3=√3

√4=2

√5=√5

√6=√6

√7=√7

√8=2√2

√9=3

√10=√10

√11=√11

√12=2√3

√13=√13

√14=√14

√15=√15

√16=4

√17=√17

√18=3√2

√19=√19

√20=2√5

√21=√21

√22=√22

√23=√23

√24=2√6

√25=5

√26=2√6

√27=3√3

√28=2√7

√29=√29

√30=√30

√31=√31

√32=4√2

√33=√33

√34=√34

√35=√35

√36=6

√37=√37

√38=√38

√40=2√10

√41=√41

√42=√42

√43=√43

√44=2√11

√45=3√5

√46=√46

√47=√47

√48=4√3

√49=7

√50=5√2

√51=√51

√52=2√13

√53=√53

√54=3√6

√55=√55

√56=2√14

√57=√57

√58=√58

√59=√59

√60=2√15

√61=√61

√62=√62

√63=3√7

√64=8

√65=√65

√66=√66

√67=√67

√68=4√17

√69=√69

√70=√70

√71=√71

√72=6√2

√73=√73

√74=√74

√75=5√3

√76=2√19

√77=√77

√78=√78

√79=√79

√80=4√5

√81=9

√82=√82

√83=√83

√84=2√21

√85=√85

√86=√86

√87=√87

√88=2√22

√89=√89

√90=3√10

√91=√91

√92=2√23

√93=√93

√94=√94

√95=√95

√96=4√12

√97=√97

√98=7√2

√99=3√11

√100=10

背了没什么用的,其实如果看不出来你可以先提出比较小的数.比如

√20=√2*√10=√2*√2*√5=2√5.这里就是先提出2然后再提2.因为2比较容易看出来.一般的

2,3,5,7,11等那些你觉的能提什么就先提出来,然后再看剩下的,提出两个一样的不就可以去

掉根号了.