Đề thi HK2 Toán 8 - THCS Cát Linh - Hà Nội - Năm 2...

A \(S = \left\{ { - 2} \right\}\)     

B \(S = \left\{ 2 \right\}\)                        

C \(S = \left\{ { \pm 2} \right\}\)            

D \(S = \left\{ {2; - 4} \right\}\)

A \(0x + 7 \ge 0\)             

B \(\left( {x - 1} \right).\left( {x + 2} \right) \le 0\)        

C \(3 - x \ge 0\)    

D \({x^2} + 2 < 0\)

A \(\frac{{20}}{3}\)           

B \(\frac{2}{3}\)    

C \(\frac{3}{{20}}\)                  

D \(\frac{3}{2}\)

A \(216c{m^2}\)

B \(36c{m^2}\)

C \(72c{m^2}\)

D \(144c{m^2}\)

A \(\begin{array}{l}a)\,\,x = 3\\b)\,\,x = 4\end{array}\)

B \(\begin{array}{l}a)\,\,x =  - 3\\b)\,\,x = 4\end{array}\)

C \(\begin{array}{l}a)\,\,x =  - 3\\b)\,\,x = - 4\end{array}\)

D \(\begin{array}{l}a)\,\,x = 3\\b)\,\,x =  - 4\end{array}\)

A \(S = \left\{ {x \in \mathbb{R}\,|\,x > 5} \right\}.\)

B \(S = \left\{ {x \in \mathbb{R}\,|\,x > 3} \right\}.\)

C \(S = \left\{ {x \in \mathbb{R}\,|\,x < 3} \right\}.\)

D \(S = \left\{ {x \in \mathbb{R}\,|\,x < 5} \right\}.\)

A ĐKXĐ: \(\left\{ \begin{array}{l}x \ne  - 1\\x \ne  \pm 3\end{array} \right.\,\,\,;\,\,\,\,P = \frac{{x + 1}}{{x + 3}}\)

B ĐKXĐ: \(\left\{ \begin{array}{l}x \ne  \pm 1\\x \ne 3\end{array} \right.\,\,\,;\,\,\,\,P = \frac{{x + 1}}{{3 - x}}\)

C ĐKXĐ: \(\left\{ \begin{array}{l}x \ne  - 1\\x \ne  \pm 3\end{array} \right.\,\,\,;\,\,\,\,P = \frac{{x + 3}}{{x + 1}}\)

D ĐKXĐ: \(\left\{ \begin{array}{l}x \ne  \pm 1\\x \ne 3\end{array} \right.\,\,\,;\,\,\,\,P = \frac{{3 - x}}{{x + 1}}\)

A \(1\)

B \(\frac{1}{2}\)

C \(\frac{1}{3}\)

D \(\frac{1}{4}\)

A \(x \in \left\{ { - 2; - 1;1} \right\}\)

B \(x \in \left\{ { - 2; - 4; - 5} \right\}\)

C \(x \in \left\{ { - 2;1;2} \right\}\)

D \(x \in \left\{ { - 3; - 4; - 5} \right\}\)

A 80 tấn

B 90 tấn

C 100 tấn

D 110 tấn