Chapter 2
Algebra and Trigonometry Real Mathematics, Real People · 560 exercises
Problem 42
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$2 x^{3}+x+4=0$$
3 step solution
Problem 42
Perform the operation and write the result in standard form. $$(\sqrt{3}+\sqrt{15} i)(\sqrt{3}-\sqrt{15} i)$$
4 step solution
Problem 42
Solve the equation (if possible). $$\frac{6}{x}-\frac{2}{x+3}=\frac{3(x+5)}{x(x+3)}$$
4 step solution
Problem 43
Solving an Equation Involving Rational Exponents Find all solutions of the equation algebraically. Check your solutions. $$\left(x^{2}-5 x-2\right)^{1 / 3}=-2$$
6 step solution
Problem 43
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solutions graphically. $$\left|\frac{x-3}{2}\right| \geq 5$$
4 step solution
Problem 43
Solve the quadratic equation by completing the square. Verify your answer graphically. $$9 x^{2}-18 x+3=0$$
4 step solution
Problem 43
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$\frac{1}{4}\left(x^{2}-10 x+17\right)=0$$
3 step solution
Problem 43
Perform the operation and write the result in standard form. $$(6+7 i)^{2}$$
4 step solution
Problem 43
Solve for the indicated variable. Area of a Triangle $$\text { Solve for } h: A=\frac{1}{2} b h$$
3 step solution
Problem 44
Solving an Equation Involving Rational Exponents Find all solutions of the equation algebraically. Check your solutions. $$\left(x^{2}-x-22\right)^{4 / 3}=16$$
4 step solution
Problem 44
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solutions graphically. $$|x+14|+3 \geq 17$$
4 step solution
Problem 44
Solve the quadratic equation by completing the square. Verify your answer graphically. $$4 x^{2}-16 x-5=0$$
4 step solution
Problem 44
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$-\frac{1}{2}\left(x^{2}-6 x+6\right)=0$$
3 step solution
Problem 44
Perform the operation and write the result in standard form. $$(5-4 i)^{2}$$
4 step solution
Problem 45
Solving an Equation Involving Rational Exponents Find all solutions of the equation algebraically. Check your solutions. $$3 x(x-1)^{1 / 2}+2(x-1)^{3 / 2}=0$$
8 step solution
Problem 45
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solutions graphically. $$10|1-x|<5$$
6 step solution
Problem 45
Solve the quadratic equation by completing the square. Verify your answer graphically. $$2 x^{2}+5 x-8=0$$
4 step solution
Problem 45
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$2 x^{3}-x^{2}-18 x+9=0$$
2 step solution
Problem 45
Perform the operation and write the result in standard form. $$(4+5 i)^{2}-(4-5 i)^{2}$$
3 step solution
Problem 45
Solve for the indicated variable. Investment at Compound Interest $$\text { Solve for } P: A=P\left(1+\frac{r}{n}\right)^{n t}$$
3 step solution
Problem 46
Solving an Equation Involving Rational Exponents Find all solutions of the equation algebraically. Check your solutions. $$4 x^{2}(x-1)^{1 / 3}+6 x(x-1)^{4 / 3}=0$$
4 step solution
Problem 46
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solutions graphically. $$3|4-5 x|<9$$
6 step solution
Problem 46
Solve the quadratic equation by completing the square. Verify your answer graphically. $$9 x^{2}-12 x-14=0$$
5 step solution
Problem 46
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$4 x^{3}+12 x^{2}-26 x-24=0$$
3 step solution
Problem 46
Solve for the indicated variable. Investment at Simple Interest Solve for \(r: A=P+P r t\)
2 step solution
Problem 46
Perform the operation and write the result in standard form. $$(1-2 i)^{2}-(1+2 i)^{2}$$
3 step solution
Problem 47
Solving an Equation Involving Fractions Find all solutions of the equation. Check your solutions. $$x=\frac{3}{x}+\frac{1}{2}$$
4 step solution
Problem 47
Use a graphing utility to graph the equation and graphically approximate the values of \(x\) that satisfy the specified inequalities. Then solve each inequality algebraically. Equation \(y=|x-3|\) Inequalities (a) \(y \leq 2\) (b) \(y \geq 4\)
5 step solution
Problem 47
(a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, and (c) verify your results algebraically. $$y=(x+3)^{2}-4$$
3 step solution
Problem 47
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$x^{5}=3 x^{3}-3$$
3 step solution
Problem 47
Solve for the indicated variable. Volume of a Right Circular Cylinder Solve for \(h: \quad V=\pi r^{2} h\)
3 step solution
Problem 47
Write the complex conjugate of the complex number. Then multiply the number by its complex conjugate. $$6-2 i$$
2 step solution
Problem 48
Solving an Equation Involving Fractions Find all solutions of the equation. Check your solutions. $$\frac{4}{x}-\frac{5}{3}=\frac{x}{6}$$
4 step solution
Problem 48
Use a graphing utility to graph the equation and graphically approximate the values of \(x\) that satisfy the specified inequalities. Then solve each inequality algebraically. Equation \(y=\left|\frac{1}{2} x+1\right|\) Inequalities (a) \(y \leq 4\) (b) \(y \geq 1\)
4 step solution
Problem 48
(a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, and (c) verify your results algebraically. $$y=1-(x-2)^{2}$$
3 step solution
Problem 48
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$x^{5}=3+2 x^{3}$$
3 step solution
Problem 48
Solve for the indicated variable. Volume of a Right Circular Cone $$\text { Solve for } h: \quad V=\frac{1}{3} \pi r^{2} h$$
3 step solution
Problem 48
Write the complex conjugate of the complex number. Then multiply the number by its complex conjugate. $$3+5 i$$
3 step solution
Problem 49
Solving an Equation Involving Fractions Find all solutions of the equation. Check your solutions. $$\frac{20-x}{x}=x$$
5 step solution
Problem 49
(a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, and (c) verify your results algebraically. $$y=-4 x^{2}+4 x+3$$
3 step solution
Problem 49
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$\frac{2}{x+2}=3$$
3 step solution
Problem 49
Use the following information. The relationship between the length of an adult's femur (thigh bone) and the height of the adult can be approximated by the linear equations $$y=0.386 x-19.20 \quad \text { Female }$$ $$y=0.442 x-29.37 \quad \text { Male }$$ where \(y\) is the length of the femur in centimeters and \(x\) is the height of the adult in centimeters. (See figure.) An anthropologist discovers a femur belonging to an adult human female. The bone is 43 centimeterss long. Estimate the height of the female.
3 step solution
Problem 49
Write the complex conjugate of the complex number. Then multiply the number by its complex conjugate. $$-1+\sqrt{7} i$$
3 step solution
Problem 50
Solving an Equation Involving Fractions Find all solutions of the equation. Check your solutions. $$4 x+1=\frac{3}{x}$$
4 step solution
Problem 50
(a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, and (c) verify your results algebraically. $$y=x^{2}+3 x-4$$
3 step solution
Problem 50
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$\frac{1}{x-3}=-2$$
3 step solution
Problem 50
Use the following information. The relationship between the length of an adult's femur (thigh bone) and the height of the adult can be approximated by the linear equations $$y=0.386 x-19.20 \quad \text { Female }$$ $$y=0.442 x-29.37 \quad \text { Male }$$ where \(y\) is the length of the femur in centimeters and \(x\) is the height of the adult in centimeters. (See figure.) From the foot bones of an adult human male, an anthropologist estimates that the person's height was 175 centimeters. A few feet away from the site where the foot bones were discovered, the anthropologist discovers a male adult femur that is 48 centimeters long. Is it likely that both the foot bones and the thigh bone came from the same person?
3 step solution
Problem 50
Write the complex conjugate of the complex number. Then multiply the number by its complex conjugate. $$-4-\sqrt{3} i$$
2 step solution
Problem 51
Solving an Equation Involving Fractions Find all solutions of the equation. Check your solutions. $$\frac{1}{x}-\frac{1}{x+1}=3$$
4 step solution
Problem 51
Use a graphing utility to determine the number of real solutions of the quadratic equation. $$x^{2}-4 x+4=0$$
3 step solution