consider the family of functions f(x) = 1 / x^p, where p is a real number. for what values of p does the…

consider the family of functions f(x) = 1 / x^p, where p is a real number. for what values of p does the integral ∫(from 0 to 1) f(x)dx exist? what is its value? for what values of p does the integral ∫(from 0 to 1) f(x)dx exist? select the correct choice below and, if necessary, fill in the answer box to complete your choice. a. the integral exists for p < 1. (type an inequality or a compound inequality.) b. the integral never exists. what is the value of the integral? select the correct choice below and, if necessary, fill in the answer box to complete your choice. a. ∫(from 0 to 1) f(x)dx = b. the integral never exists.
Answer
Explanation:
Step1: Recall power - rule for integration
The antiderivative of $x^{-p}$ is $\frac{x^{-p + 1}}{-p+1}+C$ for $p\neq1$ and $\ln(x)$ for $p = 1$. We are dealing with the improper integral $\int_{0}^{1}x^{-p}dx=\lim_{a\rightarrow0^{+}}\int_{a}^{1}x^{-p}dx$.
Step2: Evaluate the integral for $p\neq1$
$\lim_{a\rightarrow0^{+}}\int_{a}^{1}x^{-p}dx=\lim_{a\rightarrow0^{+}}\left[\frac{x^{-p + 1}}{-p + 1}\right]{a}^{1}=\lim{a\rightarrow0^{+}}\left(\frac{1}{1 - p}-\frac{a^{1 - p}}{1 - p}\right)$. This limit exists when $1-p>0$ (i.e., $p<1$) since $\lim_{a\rightarrow0^{+}}a^{1 - p}=0$ for $1 - p>0$.
Step3: Evaluate the integral for $p = 1$
When $p = 1$, $\lim_{a\rightarrow0^{+}}\int_{a}^{1}x^{-1}dx=\lim_{a\rightarrow0^{+}}[\ln(x)]{a}^{1}=\lim{a\rightarrow0^{+}}(0-\ln(a))=\infty$.
Step4: Calculate the value of the integral for $p<1$
For $p<1$, $\int_{0}^{1}x^{-p}dx=\frac{1}{1 - p}-\lim_{a\rightarrow0^{+}}\frac{a^{1 - p}}{1 - p}=\frac{1}{1 - p}$.
Answer:
A. The integral exists for $p<1$. A. $\int_{0}^{1}f(x)dx=\frac{1}{1 - p}$