1945x7+1945x2+1945

=1945x(2+7+1)

=1945x10

=19450

\(C=1+2+2^2+2^3+...+2^9\\ 2C=2+2^2+2^3+...+2^{10}\\ 2C-C=C=\left(2+2^2+2^3+...+2^{10}\right)-\left(1+2+2^2+2^3+...+2^9\right)\\ C=2^{10}-1\)

Khi đó 

\(C+1=2^{10}-1+1\\ C+1=2^{10}\)

xy-2x-2y=0

X(y-2)-2y=0

X(y-2)-2(y-2)=0-2.2

(x-2)(y-2)=-4

Suy ra -4⋮(x-2) hay x-2ϵ Ư(-4)={-4;-2;-1;1;2;4}

Ta có bảng giá trị 

\(92826-45217-24826-13217+400\\ =\left(92826-24826\right)-\left(45217+13217\right)+400\\= 68000-58434+400\\ =9566+400=9966\)

\(\dfrac{1}{3}x\dfrac{1}{9}:\dfrac{1}{10}\\ =\dfrac{1}{3}x\dfrac{1}{9}x\dfrac{10}{1}\\ =\dfrac{1x1x10}{3x9x1}\\ =\dfrac{10}{27}\)

198:[130-(19-27)²]+2024⁰

=198:[130-(-8)²]+1

=198:[130-64]+1

=198:66+1

=3+1

=4

A

\(\dfrac{2}{7}:y=\dfrac{5}{9}\\ \text{Y}=\dfrac{2}{7}:\dfrac{5}{9}\\ y=\dfrac{18}{35}\)

You must be careful when you cut food with a knife.

SAO TUẦN NÀY VẪN CHƯA CÓ BXH NHỈ ?