Chapter 10
Precalculus: Mathematics for Calculus · 524 exercises
Problem 14
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{rrr} 1 & 3 & -3 \\ 0 & 1 & 5 \end{array}\right]$$
3 step solution
Problem 14
Use the elimination method to find all solutions of the system of equations. $$\left\\{\begin{array}{c} x^{2}-y^{2}=1 \\ 2 x^{2}-y^{2}=x+3 \end{array}\right.$$
6 step solution
Problem 14
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rr}-7 & 4 \\\8 & -5\end{array}\right]$$
4 step solution
Problem 14
Find the determinant of the matrix, if it exists. $$\left[\begin{array}{rr} 2.2 & -1.4 \\ 0.5 & 1.0 \end{array}\right]$$
5 step solution
Problem 14
Perform the matrix operation, or if it is impossible, explain why. $$\left[\begin{array}{rr} 1 & 2 \\ -1 & 4 \end{array}\right]\left[\begin{array}{rrr} 1 & -2 & 3 \\ 2 & 2 & -1 \end{array}\right]$$
4 step solution
Problem 14
Two equations and their graphs are given. Find the intersection point(s) of the graphs by solving the system. (Graph cannot copy) $$\left\\{\begin{aligned} x+y &=2 \\ 2 x+y &=5 \end{aligned}\right.$$
6 step solution
Problem 14
Perform an operation on the given system that eliminates the indicated variable. Write the new equivalent system. \(\left\\{\begin{array}{rr}-5 x+2 y-3 z= & 3 \\ 10 x-3 y+z= & -20 \\ -x+3 y+z= & 8\end{array}\right.\) Eliminate the \(x\)-term from the second equation.
5 step solution
Problem 15
Find the partial fraction decomposition of the rational function. $$\frac{5}{(x-1)(x+4)}$$
5 step solution
Problem 15
Graph the inequality. $$y>x-3$$
4 step solution
Problem 15
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{llll} 1 & 2 & 8 & 0 \\ 0 & 1 & 3 & 2 \\ 0 & 0 & 0 & 0 \end{array}\right]$$
5 step solution
Problem 15
Two equations and their graphs are given. Find the intersection point(s) of the graphs by solving the system. $$\left\\{\begin{array}{l} x^{2}+y=8 \\ x-2 y=-6 \end{array}\right.$$ (GRAPH CANNOT COPY)
8 step solution
Problem 15
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rr}6 & -3 \\\\-8 & 4\end{array}\right]$$
2 step solution
Problem 15
Evaluate the minor and cofactor using the matrix \(A\). $$A=\left[\begin{array}{rrr} 1 & 0 & \frac{1}{2} \\ -3 & 5 & 2 \\ 0 & 0 & 4 \end{array}\right]$$$$M_{11}, A_{11}$$
4 step solution
Problem 15
Graph each linear system, either by hand or using a graphing device. Use the graph to determine whether the system has one solution, no solution, or infinitely many solutions. If there is exactly one solution, use the graph to find it. $$\left\\{\begin{array}{r} x-y=4 \\ 2 x+y=2 \end{array}\right.$$
4 step solution
Problem 15
Perform the matrix operation, or if it is impossible, explain why. $$\left[\begin{array}{rr} 2 & -3 \\ 0 & 1 \\ 1 & 2 \end{array}\right]\left[\begin{array}{l} 5 \\ 1 \end{array}\right]$$
3 step solution
Problem 15
Perform an operation on the given system that eliminates the indicated variable. Write the new equivalent system. \(\left\\{\begin{array}{l}2 x+y-3 z=5 \\ 2 x+3 y+z=13 \\ 6 x-5 y-z=7\end{array}\right.\) Eliminate the \(x\)-term from the third equation.
4 step solution
Problem 16
Find the partial fraction decomposition of the rational function. $$\frac{x+6}{x(x+3)}$$
7 step solution
Problem 16
Graph the inequality. $$y \leq 1-x$$
4 step solution
Problem 16
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{rrrr} 1 & 0 & -7 & 0 \\ 0 & 1 & 3 & 0 \\ 0 & 0 & 0 & 1 \end{array}\right]$$
4 step solution
Problem 16
Two equations and their graphs are given. Find the intersection point(s) of the graphs by solving the system. $$\left\\{\begin{array}{l} x-y^{2}=-4 \\ x-y=2 \end{array}\right.$$ (GRAPH CANNOT COPY)
7 step solution
Problem 16
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{ll}\frac{1}{2} & \frac{1}{3} \\\5 & 4\end{array}\right]$$
6 step solution
Problem 16
Evaluate the minor and cofactor using the matrix \(A\). $$A=\left[\begin{array}{rrr} 1 & 0 & \frac{1}{2} \\ -3 & 5 & 2 \\ 0 & 0 & 4 \end{array}\right]$$ $$M_{33}, A_{33}$$
5 step solution
Problem 16
Graph each linear system, either by hand or using a graphing device. Use the graph to determine whether the system has one solution, no solution, or infinitely many solutions. If there is exactly one solution, use the graph to find it. $$\left\\{\begin{array}{l} 2 x-y=4 \\ 3 x+y=6 \end{array}\right.$$
5 step solution
Problem 16
Perform an operation on the given system that eliminates the indicated variable. Write the new equivalent system. \(\left\\{\begin{aligned} x-3 y+2 z &=-1 \\ y+z &=-1 \\ 2 y-z &=1 \end{aligned}\right.\) Eliminate the \(y\) -term from the third equation.
7 step solution
Problem 17
Find the partial fraction decomposition of the rational function. $$\frac{12}{x^{2}-9}$$
6 step solution
Problem 17
Graph the inequality. $$2 x-y \geq-4$$
4 step solution
Problem 17
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{llll} 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 \\ 0 & 1 & 5 & 1 \end{array}\right]$$
5 step solution
Problem 17
Two equations and their graphs are given. Find the intersection point(s) of the graphs by solving the system. $$\left\\{\begin{aligned} x^{2}+y &=0 \\ x^{3}-2 x-y &=0 \end{aligned}\right.$$ (GRAPH CANNOT COPY)
6 step solution
Problem 17
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rr}0.4 & -1.2 \\\0.3 & 0.6\end{array}\right]$$
6 step solution
Problem 17
Evaluate the minor and cofactor using the matrix \(A\). $$A=\left[\begin{array}{rrr} 1 & 0 & \frac{1}{2} \\ -3 & 5 & 2 \\ 0 & 0 & 4 \end{array}\right]$$ $$M_{12}, A_{12}$$
3 step solution
Problem 17
Solve the matrix equation for the unknown matrix \(X\), or explain why no solution exists. $$\begin{array}{c}A=\left[\begin{array}{ll}4 & 6 \\\1 & 3\end{array}\right] & B=\left[\begin{array}{ll}2 & 5 \\\3 & 7\end{array}\right] \\\C=\left[\begin{array}{ll}2 & 3 \\\1 & 0 \\\0 & 2\end{array}\right] & D=\left[\begin{array}{lr}10 & 20 \\\30 & 20 \\\10 & 0\end{array}\right]\end{array}$$ $$2 X+A=B$$
5 step solution
Problem 17
Graph each linear system, either by hand or using a graphing device. Use the graph to determine whether the system has one solution, no solution, or infinitely many solutions. If there is exactly one solution, use the graph to find it. $$\left\\{\begin{array}{l} 2 x-3 y=12 \\ -x+\frac{3}{2} y=4 \end{array}\right.$$
3 step solution
Problem 17
Find the complete solution of the linear system, or show that it is inconsistent. \(\left\\{\begin{array}{rr}x-y-z= & 4 \\ 2 y+z= & -1 \\ -x+y-2 z= & 5\end{array}\right.\)
5 step solution
Problem 18
Find the partial fraction decomposition of the rational function. $$\frac{x-12}{x^{2}-4 x}$$
7 step solution
Problem 18
Graph the inequality. $$3 x-y-9<0$$
5 step solution
Problem 18
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{llll} 1 & 0 & 0 & 1 \\ 0 & 1 & 0 & 2 \\ 0 & 0 & 1 & 3 \end{array}\right]$$
5 step solution
Problem 18
Two equations and their graphs are given. Find the intersection point(s) of the graphs by solving the system. $$\left\\{\begin{aligned} x^{2}+y^{2} &=4 x \\ x &=y^{2} \end{aligned}\right.$$ (GRAPH CANNOT COPY
8 step solution
Problem 18
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{lll}4 & 2 & 3 \\\3 & 3 & 2 \\\1 & 0 & 1\end{array}\right]$$
4 step solution
Problem 18
Evaluate the minor and cofactor using the matrix \(A\). $$A=\left[\begin{array}{rrr} 1 & 0 & \frac{1}{2} \\ -3 & 5 & 2 \\ 0 & 0 & 4 \end{array}\right]$$ $$M_{13}, A_{13}$$
3 step solution
Problem 18
Solve the matrix equation for the unknown matrix \(X\), or explain why no solution exists. $$\begin{array}{c}A=\left[\begin{array}{ll}4 & 6 \\\1 & 3\end{array}\right] & B=\left[\begin{array}{ll}2 & 5 \\\3 & 7\end{array}\right] \\\C=\left[\begin{array}{ll}2 & 3 \\\1 & 0 \\\0 & 2\end{array}\right] & D=\left[\begin{array}{lr}10 & 20 \\\30 & 20 \\\10 & 0\end{array}\right]\end{array}$$ $$3 X-B=C$$
4 step solution
Problem 18
$$\left\\{\begin{aligned} 2 x+6 y &=0 \\ -3 x-9 y &=18 \end{aligned}\right.$$
3 step solution
Problem 18
Find the complete solution of the linear system, or show that it is inconsistent. \(\left\\{\begin{aligned} x-y+z &=0 \\ y+2 z &=-2 \\ x+y-z &=2 \end{aligned}\right.\)
5 step solution
Problem 19
Find the partial fraction decomposition of the rational function. $$\frac{4}{x^{2}-4}$$
6 step solution
Problem 19
Graph the inequality. $$-x^{2}+y \geq 5$$
5 step solution
Problem 19
A matrix is given. (a) Determine whether the matrix is in row-echelon form. (b) Determine whether the matrix is in reduced row-echelon form. (c) Write the system of equations for which the given matrix is the augmented matrix. $$\left[\begin{array}{rrrrr} 1 & 3 & 0 & -1 & 0 \\ 0 & 0 & 1 & 2 & 0 \\ 0 & 0 & 0 & 0 & 1 \\ 0 & 0 & 0 & 0 & 0 \end{array}\right]$$
3 step solution
Problem 19
Find all solutions of the system of equations. $$\left\\{\begin{array}{l} y+x^{2}=4 x \\ y+4 x=16 \end{array}\right.$$
4 step solution
Problem 19
Finding the Inverse of a Matrix Find the inverse of the matrix if it exists. $$\left[\begin{array}{rrr}2 & 4 & 1 \\\\-1 & 1 & -1 \\\1 & 4 & 0\end{array}\right]$$
4 step solution
Problem 19
Evaluate the minor and cofactor using the matrix \(A\). $$A=\left[\begin{array}{rrr} 1 & 0 & \frac{1}{2} \\ -3 & 5 & 2 \\ 0 & 0 & 4 \end{array}\right]$$ $$M_{23}, A_{23}$$
4 step solution
Problem 19
Solve the matrix equation for the unknown matrix \(X\), or explain why no solution exists. $$\begin{array}{c}A=\left[\begin{array}{ll}4 & 6 \\\1 & 3\end{array}\right] & B=\left[\begin{array}{ll}2 & 5 \\\3 & 7\end{array}\right] \\\C=\left[\begin{array}{ll}2 & 3 \\\1 & 0 \\\0 & 2\end{array}\right] & D=\left[\begin{array}{lr}10 & 20 \\\30 & 20 \\\10 & 0\end{array}\right]\end{array}$$ $$2(B-X)=D$$
6 step solution
Problem 19
Graph each linear system, either by hand or using a graphing device. Use the graph to determine whether the system has one solution, no solution, or infinitely many solutions. If there is exactly one solution, use the graph to find it. $$\left\\{\begin{aligned} -x+\frac{1}{2} y &=-5 \\ 2 x-y &=10 \end{aligned}\right.$$
3 step solution