Question

[Nguyễn Đức Trường]

Bài 1:

a, Đọc các kí hiệu: \(\in,\notin,\subset,\varnothing,\supset.\)

b, Cho ví dụ sử dụng các kí hiệu trên.

Bài 2:

So sánh 2 biểu thức \(A\)và \(B\), biết rằng:

\(A=\frac{2010}{2011}+\frac{2011}{2012}\);                                                       \(B=\frac{2010+2001}{2011+2012}\).

Bài 3:

Tính:

a,\(1\frac{13}{15}.\left(0,5\right)^2.3+\left(\frac{8}{15}-1\frac{19}{60}\right):1\frac{23}{24}\);

b,\(\frac{\left(\frac{11^2}{200}+0,415\right):0,01}{\frac{1}{12}-37,25+3\frac{1}{6}}\).

Answer 1

[Dũng Lê Trí]

2) \(\frac{2010+2011}{2011+2012}=\frac{2010}{2011+2012}+\frac{2011}{2011+2012}\)

\(\frac{2010}{2011}>\frac{2010}{2011+2012}\)

\(\frac{2011}{2012}>\frac{2011}{2011+2012}\)

\(\Rightarrow A>B\)

Answer 2

[Beyond The Scence]

• Bài 3:

 a) \(1\frac{13}{15}.\left(0,5\right)^2.3+\left(\frac{8}{15}-1\frac{19}{60}\right):1\frac{23}{24}\)

\(=\frac{28}{15}.\frac{1}{4}.3+-\frac{47}{60}:\frac{47}{24}\)

\(=\frac{7}{5}-\frac{2}{5}\)

\(=1\)

b)\(\frac{\left(\frac{11^2}{200}+0,415\right):0,01}{\frac{1}{12}-37,25+3\frac{1}{6}}\)

\(=\frac{\left(\frac{121}{200}+0,415\right):0,01}{\frac{1}{12}-37,25+\frac{19}{6}}\)

\(=\frac{\frac{51}{50}:\frac{1}{100}}{-34}\)

\(=\frac{102}{-34}\)

\(=-3\)