5.若 4972=5002
−a ,則a=?
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統計: A(37), B(56), C(134), D(1686), E(0) #718015
統計: A(37), B(56), C(134), D(1686), E(0) #718015
詳解 (共 6 筆)
#1110683
a=500的平方-497的平方=(500-497)*(500+497)
15
0
#1105451
(A-B)平方=A平方-2AB+B平方
497=(500-3)平方
=500平方-2(500X3)+9
=500平方-3000+9
=500平方-2991
10
0
#1350186
a=5002 − 4972
=(500-497)(500+497)
=3*997
=2991
7
0
#5871857
6
0
#1307436
(500+497)(500-497)
3
0