Chapter 3
Precalculus Mathematics for Calculus · 515 exercises
Problem 50
Find all zeros of the polynomial. $$P(x)=x^{3}-x-6$$
6 step solution
Problem 50
Find all the real zeros of the polynomial. Use the quadratic formula if necessary, as in Example \(3(a)\). $$P(x)=x^{4}+2 x^{3}-2 x^{2}-3 x+2$$
8 step solution
Problem 50
A quadratic function is given. (a) Use a graphing device to find the maximum or minimum value of the quadratic function \(f\) correct to two decimal places. (b) Find the exact maximum or minimum value of \(f,\) and compare it with your answer to part (a). $$f(x)=1+x-\sqrt{2} x^{2}$$
6 step solution
Problem 50
Use synthetic division and the Remainder Theorem to evaluate \(P(c)\). $$P(x)=x^{3}-x+1, \quad c=\frac{1}{4}$$
3 step solution
Problem 51
Evaluate the radical expression and express the result in the form \(a+b i\) $$(3-\sqrt{-5})(1+\sqrt{-1})$$
4 step solution
Problem 51
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$t(x)=\frac{3 x+6}{x^{2}+2 x-8}$$
8 step solution
Problem 51
Find all zeros of the polynomial. $$P(x)=2 x^{3}+7 x^{2}+12 x+9$$
4 step solution
Problem 51
Find all the real zeros of the polynomial. Use the quadratic formula if necessary, as in Example \(3(a)\) $$P(x)=x^{4}-7 x^{3}+14 x^{2}-3 x-9$$
9 step solution
Problem 51
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=-x^{2}+8 x, \quad[-4,12] \text { by }[-50,30]$$
6 step solution
Problem 51
Use synthetic division and the Remainder Theorem to evaluate \(P(c)\). $$P(x)=x^{3}+2 x^{2}-3 x-8, \quad c=0.1$$
6 step solution
Problem 52
Evaluate the radical expression and express the result in the form \(a+b i\) $$(\sqrt{3}-\sqrt{-4})(\sqrt{6}-\sqrt{-8})$$
6 step solution
Problem 52
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$t(x)=\frac{x-2}{x^{2}-4 x}$$
9 step solution
Problem 52
Find all zeros of the polynomial. $$P(x)=2 x^{3}-8 x^{2}+9 x-9$$
7 step solution
Problem 52
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=x^{3}-3 x^{2}, \quad[-2,5] \text { by }[-10,10]$$
6 step solution
Problem 52
Let $$\begin{aligned}P(x)=& 6 x^{7}-40 x^{6}+16 x^{5}-200 x^{4} \\\&-60 x^{3}-69 x^{2}+13 x-139\end{aligned}$$ Calculate \(P(7)\) by (a) using synthetic division and (b) substituting \(x=7\) into the polynomial and evaluating directly.
10 step solution
Problem 53
Evaluate the radical expression and express the result in the form \(a+b i\) $$\frac{2+\sqrt{-8}}{1+\sqrt{-2}}$$
7 step solution
Problem 53
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{(x-1)(x+2)}{(x+1)(x-3)}$$
8 step solution
Problem 53
Find all zeros of the polynomial. $$P(x)=x^{4}+x^{3}+7 x^{2}+9 x-18$$
6 step solution
Problem 53
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=x^{3}-12 x+9, \quad[-5,5] \text { by }[-30,30]$$
6 step solution
Problem 53
Use the Factor Theorem to show that \(x-c\) is a factor of \(P(x)\) for the given value(s) of \(c\). $$P(x)=x^{3}-3 x^{2}+3 x-1, \quad c=1$$
4 step solution
Problem 54
Evaluate the radical expression and express the result in the form \(a+b i\) $$\frac{1-\sqrt{-1}}{1+\sqrt{-1}}$$
6 step solution
Problem 54
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{2 x(x+2)}{(x-1)(x-4)}$$
8 step solution
Problem 54
Find all zeros of the polynomial. $$P(x)=x^{4}-2 x^{3}-2 x^{2}-2 x-3$$
6 step solution
Problem 54
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=2 x^{3}-3 x^{2}-12 x-32, \quad[-5,5] \text { by }[-60,30]$$
6 step solution
Problem 54
Use the Factor Theorem to show that \(x-c\) is a factor of \(P(x)\) for the given value(s) of \(c\). $$P(x)=x^{3}+2 x^{2}-3 x-10, \quad c=2$$
5 step solution
Problem 55
Evaluate the radical expression and express the result in the form \(a+b i\) $$\frac{\sqrt{-36}}{\sqrt{-2} \sqrt{-9}}$$
5 step solution
Problem 55
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{x^{2}-2 x+1}{x^{2}+2 x+1}$$
7 step solution
Problem 55
Find all zeros of the polynomial. $$P(x)=x^{5}-x^{4}+7 x^{3}-7 x^{2}+12 x-12$$
5 step solution
Problem 55
Find all the real zeros of the polynomial. Use the quadratic formula if necessary, as in Example \(3(a)\) $$P(x)=2 x^{4}+15 x^{3}+17 x^{2}+3 x-1$$
5 step solution
Problem 55
Find the local maximum and minimum values of the function and the value of \(x\) at which each occurs. State each answer correct to two decimal places. $$f(x)=x^{3}-x$$
6 step solution
Problem 55
Use the Factor Theorem to show that \(x-c\) is a factor of \(P(x)\) for the given value(s) of \(c\). $$P(x)=2 x^{3}+7 x^{2}+6 x-5, \quad c=\frac{1}{2}$$
5 step solution
Problem 56
Evaluate the radical expression and express the result in the form \(a+b i\) $$\frac{\sqrt{-7} \sqrt{-49}}{\sqrt{28}}$$
6 step solution
Problem 56
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{4 x^{2}}{x^{2}-2 x-3}$$
9 step solution
Problem 56
Find all zeros of the polynomial. $$P(x)=x^{5}+x^{3}+8 x^{2}+8$$
6 step solution
Problem 56
Find all the real zeros of the polynomial. Use the quadratic formula if necessary, as in Example \(3(a)\) $$P(x)=4 x^{5}-18 x^{4}-6 x^{3}+91 x^{2}-60 x+9$$
6 step solution
Problem 56
Find the local maximum and minimum values of the function and the value of \(x\) at which each occurs. State each answer correct to two decimal places. $$f(x)=3+x+x^{2}-x^{3}$$
4 step solution
Problem 56
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=x^{4}-18 x^{2}+32, \quad[-5,5] \text { by }[-100,100]$$
7 step solution
Problem 56
Use the Factor Theorem to show that \(x-c\) is a factor of \(P(x)\) for the given value(s) of \(c\). $$P(x)=x^{4}+3 x^{3}-16 x^{2}-27 x+63, \quad c=3,-3$$
3 step solution
Problem 57
Find all solutions of the equation and express them in the form \(a+b i\) $$x^{2}+49=0$$
4 step solution
Problem 57
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{2 x^{2}+10 x-12}{x^{2}+x-6}$$
8 step solution
Problem 57
Find all zeros of the polynomial. $$P(x)=x^{4}-6 x^{3}+13 x^{2}-24 x+36$$
8 step solution
Problem 57
A polynomial \(P\) is given. (a) Find all the real zeros of \(P\). (b) Sketch the graph of \(P\). $$P(x)=x^{3}-3 x^{2}-4 x+12$$
7 step solution
Problem 57
Find the local maximum and minimum values of the function and the value of \(x\) at which each occurs. State each answer correct to two decimal places. $$g(x)=x^{4}-2 x^{3}-11 x^{2}$$
5 step solution
Problem 57
Graph the polynomial in the given viewing rectangle. Find the coordinates of all local extrema. State each answer rounded to two decimal places. $$y=3 x^{5}-5 x^{3}+3, \quad[-3,3] \text { by }[-5,10]$$
5 step solution
Problem 57
Show that the given value(s) of \(c\) are zeros of \(P(x)\), and find all other zeros of \(P(x)\). $$P(x)=x^{3}-x^{2}-11 x+15, \quad c=3$$
4 step solution
Problem 58
Find all solutions of the equation and express them in the form \(a+b i\) $$9 x^{2}+4=0$$
4 step solution
Problem 58
Find the intercepts and asymptotes, and then sketch a graph of the rational function and state the domain and range. Use a graphing device to confirm your answer. $$r(x)=\frac{2 x^{2}+2 x-4}{x^{2}+x}$$
6 step solution
Problem 58
Find all zeros of the polynomial. $$P(x)=x^{4}-x^{2}+2 x+2$$
5 step solution
Problem 58
Find all the real zeros of the polynomial. Use the quadratic formula if necessary, as in Example \(3(a)\) $$P(x)=-x^{3}-2 x^{2}+5 x+6$$
6 step solution
Problem 58
Find the local maximum and minimum values of the function and the value of \(x\) at which each occurs. State each answer correct to two decimal places. $$g(x)=x^{5}-8 x^{3}+20 x$$
10 step solution