化简 (m+7)/(m^2+4m-21)

解答

化简

\frac{m + 7}{m ^{2} + 4 m - 21}

\frac{1}{m - 3}

求解步骤

\frac{m + 7}{m ^{2} + 4 m - 21}

因式分解

m^{2} + 4 m - 21 : (m - 3) (m + 7)

= \frac{m + 7}{( m - 3 ) ( m + 7 )}

约分:

m + 7

= \frac{1}{m - 3}

∣ x ∣ - ∣ x - 1 ∣ + ∣ x + 2 ∣ \geq 0

s im pl i f y 6 \cdot 15

s im pl i f y (5 + 7)^{2}

\frac{5 - 2}{7} > 7

h^{2} - 7 h - 8 = 0