Math Problem Statement

Guess the value of the limit (if it exists) by evaluating the function at the given numbers. (It is suggested that you report answers accurate to at least six decimal places.)

Let f(x)= (cos(5x)-cos(7x))/(x^(2))

We want to find the limit lim x is 0 f(x)= lim x is 0 (cos(5x)-cos(7x))/(x^(2))

Start by calculating the values of the function for the inputs listed in this table.

x 0.2 0.1 0.05 0.01 0.001 0.0001 0.00001

Find the f(x) inputs in the full decimal answer

Based on the values in this table, it appears

lim x is 0 (cos(5x)-cos(7x))/(x^(2)) =

Solution

Here are the calculated values of f(x)=cos(5x)cos(7x)x2f(x) = \frac{\cos(5x) - \cos(7x)}{x^2} for the given inputs:

\hline x & f(x) \\ \hline 0.2 & 9.258379 \\ 0.1 & 11.274037 \\ 0.05 & 11.815884 \\ 0.01 & 11.992601 \\ 0.001 & 11.999926 \\ 0.0001 & 11.999999 \\ 0.00001 & 11.999999 \\ \hline \end{array}$$ Based on the pattern of these values, it appears that: $$\lim_{x \to 0} \frac{\cos(5x) - \cos(7x)}{x^2} = 12$$ Would you like more details or have any questions? Here are 5 related questions: 1. Why does the limit of this function exist as $$x \to 0$$? 2. What would happen if we used higher precision for $$x$$? 3. How is L'Hôpital's Rule applied to confirm this limit? 4. What happens to the behavior of $$\cos(kx)$$ as $$x$$ approaches 0 for different values of $$k$$? 5. How does the second derivative of the cosine function relate to this limit? **Tip**: When functions involve trigonometric expressions, it can be useful to apply Taylor expansions to analyze their behavior near certain points.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Limits
Trigonometry
Calculus

Formulas

f(x) = (cos(5x) - cos(7x)) / x^2
Limit lim x → 0 f(x)

Theorems

L'Hôpital's Rule
Taylor Series Expansion

Suitable Grade Level

Grades 11-12 (Advanced High School or College Level)