limit as x approaches+0+of (36-4x^2)/x

解答

x \to + 0 + lim (\frac{36 - 4 x ^{2}}{x})

\infty

求解步骤

x \to 0 + lim (\frac{36 - 4 x ^{2}}{x})

乘开

\frac{36 - 4 x ^{2}}{x} : \frac{36}{x} - 4 x

= x \to 0 + lim (\frac{36}{x} - 4 x)

x \to a lim [f (x) \pm g (x)] = x \to a lim f (x) \pm x \to a lim g (x)

不定型除外

= x \to 0 + lim (\frac{36}{x}) - x \to 0 + lim (4 x)

x \to 0 + lim (\frac{36}{x}) = \infty

x \to 0 + lim (4 x) = 0

= \infty - 0

运用无穷大属性:

\infty - c = \infty

= \infty

\int 2 x 2 x - 1 d x

\frac{d}{d x} (\frac{1}{6 x ^{\frac{5}{6}}})

s l o p e (1, 1), (4, - \frac{1}{2})

\frac{\partial}{\partial x} (r)

t an g e n t y = \frac{- 8 x}{x ^{2} + 1}, (- 1, 4)