观察下列各式:13+23=14×4×9=14×22×3213+23+33=36=14×9×16=14×32×4213+23+33+43=100=14×16×25=14×42×52(1)计算:13+23+33+43+…+103的值;(2)猜想:13+23+33+43+…+n3的值.(3)计算:513+523+533+…+993+1003的值
观察下列各式:
13+23=×4×9=×22×32
13+23+33=36=×9×16=×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.观察下列各式:
13+23=×4×9=×22×32
13+23+33=36=×9×16=×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.33×4×9=×22×32
13+23+33=36=×9×16=×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | ×22×32
13+23+33=36=×9×16=×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | 22333×9×16=×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | ×32×42
13+23+33+43=100=×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | 223333×16×25=×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | ×42×52
(1)计算:13+23+33+43+…+103的值;
(2)猜想:13+23+33+43+…+n3的值.
(3)计算:513+523+533+…+993+1003的值.1 |
4 |
1 |
1 | 4 |
4 | 22333333333333333
答案和解析
(1)1
33+2
33+3
33+4
33+…+10
33
=
×102×112
=3025;
(2)由题意可得,
13+23+33+43+…+n3=×n2×(n+1)2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 1 |
4 |
1 |
1 | 1
4 |
4 | 4×10
2×112
=3025;
(2)由题意可得,
13+23+33+43+…+n3=×n2×(n+1)2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 2×11
2
=3025;
(2)由题意可得,
13+23+33+43+…+n3=×n2×(n+1)2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 2
=3025;
(2)由题意可得,
1
33+2
33+3
33+4
33+…+n
33=
×n2×(n+1)2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 1 |
4 |
1 |
1 | 1
4 |
4 | 4×n
2×(n+1)2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 2×(n+1)
2;
(3)513+523+533+…+993+1003
=13+23+33+43+…+1003-(13+23+33+43+…+503)
=×1002×1012-×502×512
=23876875. 2;
(3)51
33+52
33+53
33+…+99
33+100
33
=1
33+2
33+3
33+4
33+…+100
33-(1
33+2
33+3
33+4
33+…+50
33)
=
×1002×1012-×502×512
=23876875. 1 |
4 |
1 |
1 | 1
4 |
4 | 4×100
2×1012-×502×512
=23876875. 2×101
2-×502×512
=23876875. 2-
1 |
4 |
1 |
1 | 1
4 |
4 | 4×50
2×512
=23876875. 2×51
2
=23876875. 2
=23876875.
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