|3x+4|=|x-7|

解答

∣ 3 x + 4 ∣ = ∣ x - 7 ∣

x = - \frac{11}{2} or x = \frac{3}{4}

十进制

x = - 5.5, x = 0.75

求解步骤

∣ 3 x + 4 ∣ = ∣ x - 7 ∣

找到正负区间

x < - \frac{4}{3}, - \frac{4}{3} \leq x < 7, x \geq 7

对每个区间解不等式

x = - \frac{11}{2} or x = \frac{3}{4} or 无解

x = - \frac{11}{2} or x = \frac{3}{4}

f a c t or 35 x^{3} + 7 x y^{2}

f a c t or (x \cdot y)^{3} - 27 - y^{3} + 27 x^{3}

s im pl i f y - \frac{1}{5 ( 3 ( 1 ) + 2 ) ^{2}}

f a c t or 145 b^{2} + 29 b

s im pl i f y \frac{5 ( b ) ^{2}}{5 b ^{5}}