42×21÷42×21怎么简便算
42×21÷42×21怎么简便算
42x21÷42x21
=42÷42x(21x21)
=1x441
=441
42×21÷42×21简便怎么做
42×21÷42×21
=42×21×1/42×21
=21×21
=441
102×21-42简便运算怎么算
102×21-42
=102×21-2×21
=(102-2)×21
=100×21
=2100
136×21-42×18怎么简便运算
136×21-42×18
=136×21-18×2×21
=(136-36)×21
=100×21
=2100
798÷42简便演算法怎么算?
798÷42简便演算法怎么算???
分析:
运用除法的性质进行简算,
把42分成7×6
运用公式a÷(b×c)=a÷b÷c
798÷42
=798÷(7×6)
=798÷7÷6
=114÷6
=19
180×42简便算
180×42
=180×(40+2)
=180×40+180×2
=7200+360
=7560
42×108简便算
即(x^4+4x³-ax²-4x-1)-2能被x+3整除
射 商是A
则(x^4+4x³-ax²-4x-1)-2=A(x+3)
x=-3,则x+3=0
右边等于0
所以左边也等于0
x=-3
(x^4+4x³-ax²-4x-1)-2
=81-108-9a+12-1-2=0
9a=-18
a=-2
21×42不用简便方法怎么验算
21×42=882
验算:882÷42=21
或:42×21=882
42o÷21的简便运算?
420÷21
=(420÷7)÷(21÷7)
=60÷3
=20
2024-07-16 广告