Inequalities

Question Types
All Questions
gaokao 2015 Q1 Set Operations Using Inequality-Defined Sets
1. Given sets $A = \{ x \mid - 1 < x < 2 \} , B = \{ x \mid 0 < x < 3 \}$, then $A \cup B =$
A. $( - 1,3 )$
B. $( - 1,0 )$
C. $( 0,2 )$
D. $( 2,3 )$
gaokao 2015 Q1 Set Operations Using Inequality-Defined Sets
1. Let set $A = \{ \mathrm { x } / ( \mathrm { x } + 1 ) ( \mathrm { x } - 2 ) < 0 \}$, set $B = \{ \mathrm { x } / 1 < \mathrm { x } < 3 \}$, then $A \cup B =$
A. $\{ X / - 1 < X < 3 \}$ B. $\{ X / - 1 < X < 1 \}$ C. $\{ X / 1 < X < 2 \}$ D. $\{ X / 2 < X < 3 \}$
gaokao 2015 Q1 Set Operations Using Inequality-Defined Sets
1. Given the universal set $U = \{ 1,2,3,4,5,6 \}$, set $A = \{ 2,3,4 \}$, set $B = \{ 1,3,4,6 \}$, then set $A \cap C _ { U } B =$
(A) $\{ 3 \}$
(B) $\{ 2,5 \}$
(C) $\{ 1,4,6 \}$
(D) $\{ 2,3,5 \}$
gaokao 2015 Q1 Set Operations Using Inequality-Defined Sets
1. Given sets $\mathrm { P } = \left\{ x \mid x ^ { 2 } - 2 x \geq 3 \right\} , \mathrm { Q } = \{ x \mid 2 < x < 4 \}$ , then $\mathrm { P } \cap \mathrm { Q } =$ $\_\_\_\_$
gaokao 2015 Q1 Set Operations Using Inequality-Defined Sets
1. Given sets $P = \left\{ x \mid x ^ { 2 } - 2 x \geq 0 \right\} , Q = \{ x \mid 1 < x \leq 2 \}$ , then $\left( \complement _ { \mathbb{R} } P \right) \cap Q =$
A. $[0,1)$
B. $( 0,2 ]$
C. $( 1,2 )$
D. $[ 1,2 ]$
gaokao 2015 Q2 Linear Programming (Optimize Objective over Linear Constraints)
2. Let variables $x , y$ satisfy the constraint conditions $x - 2y \geq 0$, $x \leq 2$, $y \geq 0$. Then the maximum value of the objective function $z = 3x + y$ is
(A) 7
(B) 8
(C) 9
(D) 14
gaokao 2015 Q2 5 marks Linear Programming (Optimize Objective over Linear Constraints)
Variables $x, y$ satisfy the constraints $\left\{\begin{array}{c}x + 2 \geq 0, \\ x - y + 3 \geq 0, \\ 2x + y - 3 \leq 0,\end{array}\right.$ then the maximum value of the objective function $Z = x + 6y$ is
(A) 3
(B) 4
(C) 18
(D) 40
gaokao 2015 Q3 Sufficient/Necessary Conditions Between Inequality Conditions
3. Let $x \in R$. Then ``$x > 1$'' is ``$x ^ { 3 } > 1$'' a
A. sufficient but not necessary condition
B. necessary but not sufficient condition
C. necessary and sufficient condition
D. neither sufficient nor necessary condition
gaokao 2015 Q4 Sufficient/Necessary Conditions Between Inequality Conditions
4. Let $x \in \mathbb{R}$. Then ``$1 < x < 2$'' is ``$|x - 2| < 1$'' a
(A) sufficient but not necessary condition
(B) necessary but not sufficient condition
(C) necessary and sufficient condition
(D) neither sufficient nor necessary condition
gaokao 2015 Q4 5 marks Sufficient/Necessary Conditions Between Inequality Conditions
Let $x \in \mathbb{R}$. Then ``$|x - 2| < 1$'' is ``$x^2 + x - 2 > 0$'' a
(A) sufficient but not necessary condition
(B) necessary but not sufficient condition
(C) necessary and sufficient condition
(D) neither sufficient nor necessary condition
gaokao 2015 Q5 Linear Programming (Optimize Objective over Linear Constraints)
5. Given that $\mathrm { x } , \mathrm { y }$ satisfy the constraints $\left\{ \begin{array} { c } x - y \geq 0 \\ x + y - 4 \leq 0 \\ y \geq 1 \end{array} \right.$, then the maximum value of $\mathrm { z } = - 2 \mathrm { x } + \mathrm { y }$ is
(A) $- 1$
(B) $- 2$
(C) $- 5$
(D) $1$
gaokao 2015 Q5 Linear Programming (Optimize Objective over Linear Constraints)
5. If variables $x$ and $y$ satisfy the constraint conditions $\left\{ \begin{array} { l } x + 2 y \geq 0 , \\ x - y \leq 0 , \\ x - 2 y + 2 \geq 0 , \end{array} \right.$ then the minimum value of $z = 2 x - y$ equals
A. $- \frac { 5 } { 2 }$
B. $- 2$
C. $- \frac { 3 } { 2 }$
D. 2
gaokao 2015 Q10 5 marks Linear Programming (Optimize Objective over Linear Constraints)
If the system of inequalities $\left\{ \begin{array} { c } x + y - 2 \leq 0 \\ x + 2 y - 2 \geq 0 \\ x - y + 2 m \geq 0 \end{array} \right.$ represents a triangular region with area equal to $\frac { 4 } { 3 }$, then the value of $m$ is
(A) $-3$
(B) $1$
(C) $\frac { 4 } { 3 }$
(D) $3$
gaokao 2015 Q14 Linear Programming (Optimize Objective over Linear Constraints)
14. If $x , y$ satisfy the constraint conditions $\left\{ \begin{array} { c } x + y - 5 \leq 0 \\ 2 x - y - 1 \geq 0 \\ x - 2 y + 1 \leq 0 \end{array} \right.$, then the maximum value of $z = 2 x + y$ is $\_\_\_\_$ .
gaokao 2015 Q14 Linear Programming (Optimize Objective over Linear Constraints)
If $\mathrm { x } , \mathrm { y }$ satisfy the constraint conditions $\left\{ \begin{array} { l } x - y + 1 \geqslant 0 , \\ x - 2 y \leqslant 0 , \\ x + 2 y - 2 \leqslant 0 , \end{array} \right.$ then the maximum value of $z = x + y$ is $\_\_\_\_$ .
gaokao 2015 Q14 Optimization Subject to an Algebraic Constraint
14. Given that real numbers $x , y$ satisfy $x ^ { 2 } + y ^ { 2 } \leq 1$ , then the maximum value of $| 2 x + y - 4 | + | 6 - x - 3 y |$ is $\_\_\_\_$ .
gaokao 2016 Q1 5 marks Set Operations Using Inequality-Defined Sets
Let $A = \left\{ x \mid x ^ { 2 } - 4 x + 3 < 0 \right\} , B = \{ x \mid 2 x - 3 > 0 \}$, then $A \cap B =$
(A) $\left( - 3 , - \frac { 3 } { 2 } \right)$
(B) $\left( - 3 , \frac { 3 } { 2 } \right)$
(C) $\left( 1 , \frac { 3 } { 2 } \right)$
(D) $\left( \frac { 3 } { 2 } , 3 \right)$
gaokao 2017 Q1 5 marks Set Operations Using Inequality-Defined Sets
Given sets $A = \{ x \mid x < 2 \}$, $B = \{ x \mid 3 - 2x > 0 \}$, then
A. $A \cap B = \{ x \mid x \leq \frac{3}{2} \}$
B. $A \cap B = \varnothing$
C. $A \cup B = \left\{ x \left\lvert \, x < \frac{3}{2} \right. \right\}$
D. $A \cup B = \mathbf{R}$
gaokao 2017 Q5 Solve Polynomial/Rational Inequality for Solution Set
If $a > 1$, then the range of values of $x$ satisfying $\log_a(x^2 - 2) < \log_a x$ is
A. $(\sqrt{2}, +\infty)$
B. $(\sqrt{2}, 2)$
C. $(1, \sqrt{2})$
D. $(1, 2)$
gaokao 2017 Q7 5 marks Linear Programming (Optimize Objective over Linear Constraints)
Let $x, y$ satisfy the constraint conditions $\left\{ \begin{array}{l} x - y \geq 1 \\ y \geq 0 \end{array} \right.$. Then the maximum value of $z = x + y$ is
A. 0
B. 1
C. 2
D. 3
gaokao 2017 Q7 Linear Programming (Optimize Objective over Linear Constraints)
Let $x, y$ satisfy the linear constraints $\left\{\begin{array}{l} 2x - 3y + 3 \geq 0, \\ y + 3 \geq 0, \\ 3x - 3 \leq 0 \end{array}\right.$ and let $z = 2x + y$. The minimum value of $z$ is
A. $-15$
B. $-9$
C. $1$
D. $9$
gaokao 2017 Q14 5 marks Linear Programming (Optimize Objective over Linear Constraints)
Let $x$ and $y$ satisfy the constraints $\left\{ \begin{array} { l } x + 2 y \leqslant 1, \\ 2 x + y \geqslant - 1, \\ x - y \leqslant 0, \end{array} \right.$ then the minimum value of $z = 3 x - 2 y$ is \_\_\_\_
gaokao 2017 Q23 10 marks Quadratic Inequality Holding for All x (or a Restricted Domain)
[Optional 4-5: Inequalities] (10 points)
Given functions $f(x) = -x^2 + ax + 4$ and $g(x) = |x + 1| + |x - 1|$.
(2) If the solution set of the inequality $f(x) \geq g(x)$ contains $[-1, 1]$, find the range of values for $a$.
gaokao 2018 Q2 5 marks Set Operations Using Inequality-Defined Sets
Given the set $A = \left\{ x \mid x ^ { 2 } - x - 2 > 0 \right\}$, then $\mathrm { C } _ { \mathrm { R } } A =$
A. $\{ x \mid - 1 < x < 2 \}$
B. $\{ x \mid - 1 \leqslant x \leqslant 2 \}$
C. $\{ x \mid x < - 1 \} \cup \{ x \mid x > 2 \}$
D. $\{ x \mid x \leqslant - 1 \} \cup \{ x \mid x \geqslant 2 \}$
gaokao 2018 Q13 5 marks Linear Programming (Optimize Objective over Linear Constraints)
If $x , y$ satisfy the constraints $\left\{ \begin{array} { l } x - 2 y - 2 \leqslant 0 , \\ x - y + 1 \geqslant 0 , \\ y \leqslant 0 , \end{array} \right.$ then the maximum value of $z = 3 x + 2 y$ is $\_\_\_\_$