x - 1 / 2018 + x-9 / 503 = x - 3 / 1008 + x - 9 / 670
Tìm x, biết:
\(\frac{x-1}{2018}\)+ \(\frac{x-7}{503}\)= \(\frac{x-3}{1008}\)+ \(\frac{x-9}{670}\)
Chứng minh :
1/2 + 1/4 + 1/8 + ...+ 1/1024 < 1
1/2 +1/3 +1/4 +....+1/63 >2
\(\frac{x-1}{2018}+\frac{x-7}{503}=\frac{x-3}{1008}+\frac{x-9}{670}\)
\(\Leftrightarrow\frac{x-1}{2018}-1+\frac{x-7}{503}-4=\frac{x-3}{1008}-2+\frac{x-9}{670}-3\)
\(\Leftrightarrow\left(x-2019\right)\left(\frac{1}{2018}+\frac{1}{503}-\frac{1}{1008}-\frac{1}{670}\right)=0\)
\(\Rightarrow x=2019\)
#CBHT
Đặt A =1/2+1/4+1/8+...+1/1024
2A= 1+1/2+1/4+...+1/512
A= 1-1/1024
=>A<1hay ...
(4/3)^2018÷(16/9)^1008-x=0,6^3÷0,2^3
\(\left(\frac{4}{3}\right)^{2018}:\left(\frac{16}{9}\right)^{1008}-x=0,6^3:0,2^3\)
\(\Leftrightarrow\left[\left(\frac{4}{3}\right)^2\right]^{1009}:\left(\frac{16}{9}\right)^{1008}-x=27\)
\(\Leftrightarrow\left(\frac{16}{9}\right)^{1009}:\left(\frac{16}{9}\right)^{1008}-x=27\)
\(\Leftrightarrow\frac{16}{9}-x=27\)
\(\Leftrightarrow x=\frac{-227}{9}\)
Vậy x = \(\frac{-227}{9}\)
9.2^x.(2^1005-2^1002+.....+2^3-1)=2^1008-1 *
A=2^1005-2^1002+...+2^3-1 2^3 .
A=2^2.(2^1005-2^1002+......+2^3-1) 8.
A=2^1008-2^1005+.....+2^6-2^3
A=2^1005-2^1002+.....+2^3-1 8.A+A=2^1008-1 9.
A=2^1008-1
Thay 9.a=2^1008-1 vào * ta có: 2^x.(2^1008-1)=2^1008-1
2^x=(2^1008-1):(2^1008-1)
2^x=1
2^x=2^0
x=0
vậy x=0
Lập đề bài cho bài toán này
\(\frac{1}{2}-\left(\frac{1}{1+2}+\frac{1}{1+2+3}+\frac{1}{1+2+3+4}+...+\frac{1}{1+2+3+...+x}\right)=-\frac{503}{1008}\)tìm x
1.tính bằng hai cách
(2/3-4/5)x25 3/4x2/503/4x2/7
2.tìm x
x:2/5=2/3 x:2/3=4/9
2012 x 20 - 1006 x 18 x 2 - 503 x 4
2012+2011 x a x (2012 - 503 x 4 ) + 2012 x 9
tinh nhanh nha mg dung m tich nha
a = 2012 * 20 - 1006 * 2 * 18 - 503 * 4
= 2012 * 20 - 2012 * 18 - 2012
= 2012* 20 - 2012 * 18 - 2012 *1
= 2012* ( 20-18-1)
= 2012* 1 = 2012
Đây nek
thank ban phuong pham nha
c1: \(\frac{1}{2}-\left(\frac{1}{1+2}+\frac{1}{1+2+3}+\frac{1}{1+2+3+4}+...+\frac{1}{1+2+3+...+x}\right)=-\frac{503}{1008}\)
tim x : (x+2)/2019 + (x+3)/2018 + (x+4)/2017 + (x+5)/1008 + (x+2076)/11 = 0
lam nhu the nao giup minh voi
Đặt tính rồi tính.
1041 x 6 1008 x 9 1107 x 8 1619 x 5