Tính nhanh :
1998 . 1996 + 1997 . 11 + 1985
----------------------------------------------
1997 .1996 - 1995 . 1996
Tính nhanh biểu thức sau:
A= 1998*1996+1997*11+1985/1997*1996-1995*1996
1998×1996+1997×11+1985
1997×1996-1995×1996=?
1998 x 1996 + 1997 x 11 + 1985 : 1997 x 1996 - 1995 x 1996
1998*1996+1997*11+1985
1997*1996-1995*1996
1998 x 1996 + 1997 x 11 + 1985
= 3988008 + 21967 + 1985
= 4009975 + 1985
= 4011960
b. 1997 x 1996 - 1995 x 1996
= 1996 x (1997 - 1995)
= 1996 x 2
= 3992
tính một cách hợp lí
1998 * 1996 + 1997 * 11 + 1985 / 1997 * 1996 - 1995 * 1996 =
ai giúp mình với
Trả lời :
\(\frac{1998\times1996+1997\times11+1985}{1997\times1996-1995\times1996}\)
\(=\frac{1998\times1996+\left(1996+1\right)\times11+1985}{1996\times\left(1997-1995\right)}\)
\(=\frac{1998\times1996+1996\times11+11+1985}{1996\times2}\)
\(=\frac{1998\times1996+1996\times11+1996}{1996\times2}\)
\(=\frac{1996\times\left(1998+11+1\right)}{1996\times2}\)
\(=\frac{2010}{2}\)
\(=1005\)
1998*996+1997*11+1985/1997*1996-1995*1996
1998 x 1996 + 1997 x 11 + 1985/1997 x 1996 - 1995 x1996
Tính nhanh: a) 1988*1996+1997+1985/1997*1996-1995*1996 b) 989898/454545 - 31313131/15151515
998*1996+1997*11+1985/1997*1996-1995*1996