Khong thuc hien phep tinh o mau, hay so sanh cac phan so sau
b) M = \(\frac{53.71-18}{71.555552+53}\); N=\(\frac{54.107-53}{53.107+54}\)va P=\(\frac{135.269-133}{134.269+135}\)
Tinh nhanh:
\(\frac{6}{2.5}+\frac{6}{5.8}+\frac{6}{8.11}+......+\frac{6}{299.302};\)
So sanh cac phan so sau ma khong can thuc hien cac phep tinh o mau
\(A=\frac{54.107-53}{53.107+54}\) \(B=\frac{135.269-133}{134.269+135}\)
\(\frac{6}{2.5}+\frac{6}{5.8}+\frac{6}{8.11}+...+\frac{6}{299.302}\)
\(=2\left(\frac{3}{2.5}+\frac{3}{5.8}+\frac{3}{8.11}+..+\frac{3}{299.302}\right)\)
\(=2\left(\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{299}-\frac{1}{302}\right)\)
\(=2\left(\frac{1}{2}-\frac{1}{302}\right)=2.\frac{75}{151}=\frac{150}{151}\)
\(A=\frac{54.107-53}{53.107+54}=\frac{\left(53+1\right).107-53}{53.107+54}\)
\(=\frac{53.107+107-53}{53.107+54}=\frac{53.107+54}{53.107+54}=1\)
\(B=\frac{135.269-133}{134.269+135}=\frac{\left(134+1\right)269-133}{134.269+135}\)
\(=\frac{134.269+269-133}{134.269+135}=\frac{134.269+136}{134.269+135}>1\)
\(\Rightarrow B>A\)
khong thuc hien phep tinh o mau , hay so sanh cac phan so sau
a) A = \(\frac{244.395-151}{244+395.243}\)va B=\(\frac{423134.846267-423133}{4423133.846267+423134}\)
Ai giup minh voi
ban cu chon hen xui di 50xui va 50mayman
Không thực hiện phep tinh ở mau de so sanh cac pso sau
a,A=244.395-151/244+395.243
và B=423134.846267-423133/423133.846267+423134
b,M=53.71-18/71.52+53
N=54.107-53/53.107+54
P=135.269-133/134.269+135
Khong thuc hien phep tinh cong , hay so sanh tong M = 21/23 + 12/37 voi N = 57/59 + 3/8.
khong thuc hien phep tinh , hay so sanh : 99 x 99 va 98 x 100
Ta có: 99x99=99x(98+1) = 99x98+99
98x100= 98x(99+1) = 98x99+98
Ta có: 98x99=98x99 mà 99> 98 => 99x99>98x100
khong thuc hien phep tinh hay so sanh hai tich sau
2008 va 2002;2006 va 2004
Gọi 2008x2002 là A,gọi 2006x2004 là B
Xét vế A,ta thấy :
A = 2008 x 2002 = ( 2006 + 2 ) x 2002 = 2006 x 2002 + 2 x 2002
Xét vế B,ta thấy
B = 2006 x 2004 = 2006 x ( 2002 + 2 ) = 2006 x 2002 + 2006 x 2
Vì 2006 x 2002 = 2006 x 2002 và 2 x 2002 < 2006 x2 nên 2008 x 2002 < 2006 x 2004
Ta có: 2008.2002 = (2006 + 2) . 2002
=2006 . 2002 + 2002 . 2
=2006 . 2002 + 4004
2006.2004 = 2006 . (2002 + 2)
=2006 . 2002 + 4012
Ta thấy: 2006 . 2002 +4004 < 2006 . 2002 + 4012 (4004 < 4012)
=>2008 . 2002 < 2006 . 2004
khong thuc hien phep tinh hay so sanh
A=35.53-18
B=35+53.34
giup minh nhanh nhe ai dung minh tick
khong thuc hien phep tinh hay so sanh A va B
A = 36 x 63 - 27
B = 36 + 63 x 35
cho 2 bieu thuc:A=101 x50 ;B= 50x49+53x50
khong thuc hien tinh hay su dung tinh chat cua phep tinh de so sanh gia tri so cua A va B