|2x-5|<= 13

解答

∣ 2 x - 5 ∣ \leq 13

- 4 \leq x \leq 9

间隔符号

[- 4, 9]

求解步骤

∣ 2 x - 5 ∣ \leq 13

使用绝对值运算法则: 若

∣ u ∣ \leq a, a > 0

，则

- a \leq u \leq a

- 13 \leq 2 x - 5 \leq 13

2 x - 5 \geq - 13 and 2 x - 5 \leq 13

x \geq - 4 and x \leq 9

合并重叠的区间

- 4 \leq x \leq 9

s im pl i f y (3 x^{2} - 4 y^{2} + 5 x y) + (2 y^{2} - 3 x^{2} - 4 x y)

f a c t or x^{3} - 2 x^{2} - 33 x + 90

s im pl i f y \frac{5}{6} \cdot 12

f a c t or 21 n^{2} + 45 n - 54

f a c t or x^{3} + 6 x^{2} + 5 x