Problem 85
Numerical, Graphical, and Analytic Analysis Consider the functions \(f(x)=x\)
and \(g(x)=\tan x\) on the interval \((0, \pi / 2)\)
(a) Complete the table and make a conjecture about which is the greater
function on the interval \((0, \pi / 2)\).
$$
\begin{array}{|l|l|l|l|l|l|l|}
\hline x & 0.25 & 0.5 & 0.75 & 1 & 1.25 & 1.5 \\
\hline f(x) & & & & & & \\
\hline g(x) & & & & & & \\
\hline
\end{array}
$$
(b) Use a graphing utility to graph the functions and use the graphs to make a
conjecture about which is the greater function on the interval \((0, \pi / 2)\).
(c) Prove that \(f(x)
Problem 86
Coughing forces the trachea (windpipe) to contract, which affects the velocity
\(v\) of the air passing through the trachea. The velocity of the air during
coughing is
\(v=k(R-r) r^{2}, \quad 0 \leq r
Problem 88
The function \(s(t)\) describes the motion of a particle moving along a line. For each function, (a) find the velocity function of the particle at any time \(t \geq 0\), (b) identify the time interval(s) when the particle is moving in a positive direction, (c) identify the time interval(s) when the particle is moving in a negative direction, and (d) identify the time(s) when the particle changes its direction. $$ s(t)=t^{2}-7 t+10 $$
Problem 89
The function \(s(t)\) describes the motion of a particle moving along a line. For each function, (a) find the velocity function of the particle at any time \(t \geq 0\), (b) identify the time interval(s) when the particle is moving in a positive direction, (c) identify the time interval(s) when the particle is moving in a negative direction, and (d) identify the time(s) when the particle changes its direction. $$ s(t)=t^{3}-5 t^{2}+4 t $$
Problem 90
The function \(s(t)\) describes the motion of a particle moving along a line. For each function, (a) find the velocity function of the particle at any time \(t \geq 0\), (b) identify the time interval(s) when the particle is moving in a positive direction, (c) identify the time interval(s) when the particle is moving in a negative direction, and (d) identify the time(s) when the particle changes its direction. $$ s(t)=t^{3}-20 t^{2}+128 t-280 $$
Problem 100
Determine whether the statement is true or false. If it is false, explain why or give an example that shows it is false. An \(n\) th-degree polynomial has at most \((n-1)\) critical numbers.
Problem 100
Consider \(\lim _{x \rightarrow-\infty} \frac{3 x}{\sqrt{x^{2}+3}}\). Use the definition of limits at infinity to find values of \(N\) that correspond to (a) \(\varepsilon=0.5\) and (b) \(\varepsilon=0.1\).