Math Problem Statement

Evaluate the limit lim (x -> 0) (1 - cos(x)) / x.

Solution

The given image contains the following mathematical expression:

limx01cos(x)x\lim_{x \to 0} \frac{1 - \cos(x)}{x}

To evaluate this limit, we can apply L'Hopital's Rule, since directly substituting x=0x = 0 results in an indeterminate form 00\frac{0}{0}.

Step-by-Step Solution:

  1. Apply L'Hopital's Rule: This rule is used for limits of the form 00\frac{0}{0} or \frac{\infty}{\infty}. It states that:

limxaf(x)g(x)=limxaf(x)g(x)\lim_{x \to a} \frac{f(x)}{g(x)} = \lim_{x \to a} \frac{f'(x)}{g'(x)}

if the limit on the right exists.

In this case, both the numerator 1cos(x)1 - \cos(x) and the denominator xx approach 0 as x0x \to 0. So we can apply L'Hopital's Rule by differentiating the numerator and the denominator:

  • Derivative of the numerator: ddx[1cos(x)]=sin(x)\frac{d}{dx}[1 - \cos(x)] = \sin(x)
  • Derivative of the denominator: ddx[x]=1\frac{d}{dx}[x] = 1
  1. Rewrite the limit:

limx01cos(x)x=limx0sin(x)1\lim_{x \to 0} \frac{1 - \cos(x)}{x} = \lim_{x \to 0} \frac{\sin(x)}{1}

  1. Evaluate the limit:

As x0x \to 0, sin(x)0\sin(x) \to 0. Hence:

limx0sin(x)=0\lim_{x \to 0} \sin(x) = 0

So, the value of the original limit is:

0\boxed{0}

Would you like more details, or do you have any specific questions?


Here are five questions to extend this topic:

  1. What is L'Hopital's Rule, and when can it be applied?
  2. How would the limit change if the denominator were x2x^2 instead of xx?
  3. Can you explain why the function 1cos(x)x\frac{1 - \cos(x)}{x} approaches 0 as x0x \to 0?
  4. How can you approximate cos(x)\cos(x) for small values of xx using a Taylor series?
  5. What are some alternative methods to evaluate trigonometric limits without L'Hopital's Rule?

Tip: Always check if the limit leads to an indeterminate form like 00\frac{0}{0} before applying L'Hopital's Rule!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Limits
Trigonometry
L'Hopital's Rule

Formulas

L'Hopital's Rule
Derivative of cos(x)

Theorems

L'Hopital's Rule

Suitable Grade Level

Undergraduate Calculus