limit as x approaches 5/2 of (4x^2-25)/(2x-5)

解答

x \to \frac{5}{2} lim (\frac{4 x ^{2} - 25}{2 x - 5})

10

求解步骤

x \to \frac{5}{2} lim (\frac{4 x ^{2} - 25}{2 x - 5})

化简

\frac{4 x ^{2} - 25}{2 x - 5} : 2 x + 5

= x \to \frac{5}{2} lim (2 x + 5)

代入值

x = \frac{5}{2}

= 2 \cdot \frac{5}{2} + 5

化简

2 \cdot \frac{5}{2} + 5 : 10

= 10

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