1.(2025·启东一模)—2025的绝对值是 (
A.-2025
B.2025
C.$-\dfrac{1}{2025}$
D.$\dfrac{1}{2025}$
B
)A.-2025
B.2025
C.$-\dfrac{1}{2025}$
D.$\dfrac{1}{2025}$
答案:1.B
2.下面各数中,绝对值最小的是 (
A.-3
B.-1
C.+3
D.0
D
)A.-3
B.-1
C.+3
D.0
答案:2.D
3.(2025·汉川模拟)下列计算结果为7的是 (
A.-(+7)
B.+(-7)
C.-(-7)
D.-|-7|
C
)A.-(+7)
B.+(-7)
C.-(-7)
D.-|-7|
答案:3.C
4.若$|x|=2$,则$x$的值为(
A.$-2$
B.$\frac{1}{2}$
C.$2$
D.$\pm2$
D
)A.$-2$
B.$\frac{1}{2}$
C.$2$
D.$\pm2$
答案:4.D
5.当$|x|=-x$时,则$x$一定是(
A.负数
B.正数
C.负数或0
D.0
C
)A.负数
B.正数
C.负数或0
D.0
答案:5.C
6.化简下列各式:
(1) $\left| -\dfrac{2}{3} \right|$;
(2) $-\left| -1\dfrac{2}{3} \right|$;
(3) $-\left| -(-0.7) \right|$;
(4) $-\left| +2.5 \right|$;
(5) $\left| -(-3) \right|$;
(6) $-\left| -(+2025) \right|$。
(1) $\left| -\dfrac{2}{3} \right|$;
(2) $-\left| -1\dfrac{2}{3} \right|$;
(3) $-\left| -(-0.7) \right|$;
(4) $-\left| +2.5 \right|$;
(5) $\left| -(-3) \right|$;
(6) $-\left| -(+2025) \right|$。
答案:6.(1)$\dfrac{2}{3}$ (2)$-1\dfrac{2}{3}$ (3)$-0.7$ (4)$-2.5$ (5)3
(6)$-2025$
(6)$-2025$
7. 计算:
(1)$2025 - |-2023|$;
(2)$2 - \left| -\dfrac{4}{5} \right|$;
(3)$|-4| + |+3|$;
(4)$\left| -\dfrac{4}{3} \right| - \left| \dfrac{1}{3} \right|$;
(5)$\left| -( +\dfrac{1}{2} ) \right| + |-0.3|$;
(6)$|-16| + |-24| + |-30|$;
(7)$\left| -3\dfrac{1}{3} \right| ÷ \left| -1\dfrac{1}{4} \right| × |-12|$。
(1)$2025 - |-2023|$;
(2)$2 - \left| -\dfrac{4}{5} \right|$;
(3)$|-4| + |+3|$;
(4)$\left| -\dfrac{4}{3} \right| - \left| \dfrac{1}{3} \right|$;
(5)$\left| -( +\dfrac{1}{2} ) \right| + |-0.3|$;
(6)$|-16| + |-24| + |-30|$;
(7)$\left| -3\dfrac{1}{3} \right| ÷ \left| -1\dfrac{1}{4} \right| × |-12|$。
答案:7.(1)2 (2)$1\dfrac{1}{5}$ (3)7 (4)1 (5)0.8 (6)70 (7)32