Before applying L 'Bida's law, two tasks must be completed: whether the limits of numerator and denominator are all equal to zero (or infinity); Whether the denominator of the numerator is differentiable within the defined area.
If these two conditions are satisfied, then take derivative and judge whether the limit after derivative exists: if it exists, get the answer directly; If it does not exist, it means that this infinitive cannot be solved by L'H?pital's law. If it is uncertain, that is, the result is still undecided, then continue to use the Lobida rule on the basis of verification.
Extended data
The thinking function of extreme thinking;
Extreme thoughts are widely used in modern mathematics and even physics, which is determined by its inherent thinking function. The thought of limit reveals the unity of opposites between variables and constants, infinity and finiteness, which is the application of the law of unity of opposites of materialist dialectics in the field of mathematics.
With the help of limit thought, people can know infinity from finiteness, change from invariability, curve from linear formation, qualitative change from quantitative change and accuracy from approximation.
The two concepts of "infinity" and "finiteness" are different in essence, but they are related. Infinity is the concept of abstract thinking in the brain, which exists in the brain. "finiteness" is the mapping of ever-changing things that exist objectively, and "infinity" that conforms to the laws of objective reality belongs to the whole. According to axioms, the whole is greater than the local thinking.
Baidu Encyclopedia-Lobida Rule
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