17. - / 5.92 points determine whether ( f^{prime}(0) ) exists. ( f(x)=left{\begin{array}{ll}x^{2} sin…

17. - / 5.92 points determine whether ( f^{prime}(0) ) exists. ( f(x)=left{\begin{array}{ll}x^{2} sin \frac{7}{x} & \text { if } x \neq 0 \\ 0 & \text { if } x=0end{array}\right. ) ( \bigcirc f^{prime}(0) ) does exist. ( \bigcirc f^{prime}(0) ) does not exist.
Answer
Explanation:
Step1: Recall the definition of the derivative
The derivative of a function (f(x)) at (x = a) is given by (f^{\prime}(a)=\lim_{x\rightarrow a}\frac{f(x)-f(a)}{x - a}). For (a = 0) and (f(0)=0), we have (f^{\prime}(0)=\lim_{x\rightarrow0}\frac{f(x)-f(0)}{x-0}=\lim_{x\rightarrow0}\frac{x^{2}\sin\frac{7}{x}-0}{x}).
Step2: Simplify the limit expression
Simplify (\lim_{x\rightarrow0}\frac{x^{2}\sin\frac{7}{x}}{x}). Using the rule of fraction simplification (\frac{x^{2}\sin\frac{7}{x}}{x}=x\sin\frac{7}{x}) for (x\neq0).
Step3: Use the Squeeze Theorem
We know that (- 1\leqslant\sin\frac{7}{x}\leqslant1) for (x\neq0). Multiply each part of the inequality by (x) (when (x>0), the inequality direction remains; when (x < 0), the inequality direction is reversed). We get (-|x|\leqslant x\sin\frac{7}{x}\leqslant|x|). Since (\lim_{x\rightarrow0}-|x| = 0) and (\lim_{x\rightarrow0}|x|=0), by the Squeeze Theorem (\lim_{x\rightarrow0}x\sin\frac{7}{x}=0).
Answer:
(f^{\prime}(0)) does exist.