Chapter 11
Algebra and Trigonometry · 426 exercises
Problem 26
\(21-48=\) Solve the system, or show that it has no solution. If the system has infinitely many solutions, express them in the ordered-pair form given in Example \(6 .\) $$ \left\\{\begin{array}{r}{x+y=7} \\ {2 x-3 y=-1}\end{array}\right. $$
6 step solution
Problem 26
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} 2 y+z &=3 \\ 5 x+4 y+3 z &=-1 \\ x-3 y &=-2 \end{aligned}\right. $$
9 step solution
Problem 26
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \begin{array}{ll}{\text { (a) } D H} & {\text { (b) } H D}\end{array} $$
4 step solution
Problem 27
Evaluate the determinant, using row or column operations whenever possible to simplify your work. $$ \left|\begin{array}{llll}{0} & {0} & {4} & {6} \\ {2} & {1} & {1} & {3} \\\ {2} & {1} & {2} & {3} \\ {3} & {0} & {1} & {7}\end{array}\right| $$
6 step solution
Problem 27
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{aligned} x & \geq 0 \\ y & \geq 0 \\ 3 x+5 y & \leq 15 \\ 3 x+2 y & \leq 9 \end{aligned}\right. $$
6 step solution
Problem 27
The system of linear equations has a unique solution. Find the solution using Gaussian elimination or Gauss-Jordan elimination. $$ \left\\{\begin{array}{l}{2 x-3 y-z=13} \\ {-x+2 y-5 z=6} \\ {5 x-y-z=49}\end{array}\right. $$
5 step solution
Problem 27
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{array}{l}{x^{2}+y^{2}=9} \\ {x^{2}-y^{2}=1}\end{array}\right. $$
4 step solution
Problem 27
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{x^{2}+1}{x^{3}+x^{2}} $$
7 step solution
Problem 27
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} x+2 y-z &=1 \\ 2 x+3 y-4 z &=-3 \\ 3 x+6 y-3 z &=4 \end{aligned}\right. $$
3 step solution
Problem 27
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \left(\begin{array}{llll}{\text { a) }} & {A H} & {} & {\text { (b) }} & {H A}\end{array}\right. $$
4 step solution
Problem 28
Evaluate the determinant, using row or column operations whenever possible to simplify your work. $$ \left|\begin{array}{rrrr}{-2} & {3} & {-1} & {7} \\ {4} & {6} & {-2} & {3} \\\ {7} & {7} & {0} & {5} \\ {3} & {-12} & {4} & {0}\end{array}\right| $$
5 step solution
Problem 28
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{aligned} x &>2 \\ y &<12 \\ 2 x-4 y &>8 \end{aligned}\right. $$
4 step solution
Problem 28
The system of linear equations has a unique solution. Find the solution using Gaussian elimination or Gauss-Jordan elimination. $$ \left\\{\begin{array}{l}{10 x+10 y-20 z=60} \\ {15 x+20 y+30 z=-25} \\ {-5 x+30 y-10 z=45}\end{array}\right. $$
6 step solution
Problem 28
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{aligned} x^{2}+2 y^{2} &=2 \\ 2 x^{2}-3 y &=15 \end{aligned}\right. $$
6 step solution
Problem 28
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{3 x^{2}+5 x-13}{(3 x+2)\left(x^{2}-4 x+4\right)} $$
7 step solution
Problem 28
\(21-48=\) Solve the system, or show that it has no solution. If the system has infinitely many solutions, express them in the ordered-pair form given in Example \(6 .\) $$ \left\\{\begin{array}{l}{4 x-3 y=28} \\ {9 x-y=-6}\end{array}\right. $$
7 step solution
Problem 28
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \begin{array}{ll}{\text { (a) } B C} & {\text { (b) } B F}\end{array} $$
3 step solution
Problem 28
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} x+2 y-z &=1 \\ 2 x+3 y-4 z &=-3 \\ 3 x+6 y-3 z &=4 \end{aligned}\right. $$
3 step solution
Problem 29
Evaluate the determinant, using row or column operations whenever possible to simplify your work. $$ \left|\begin{array}{ccccc}{1} & {2} & {3} & {4} & {5} \\ {0} & {2} & {4} & {6} & {8} \\ {0} & {0} & {3} & {6} & {9} \\ {0} & {0} & {0} & {4} & {8} \\\ {0} & {0} & {0} & {0} & {5}\end{array}\right| $$
3 step solution
Problem 29
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{array}{l}{y \leq 9-x^{2}} \\ {x \geq 0, \quad y \geq 0}\end{array}\right. $$
6 step solution
Problem 29
Determine whether the system of linear equations is inconsistent or dependent. If it is dependent, find the complete solution. $$ \left\\{\begin{aligned} x+y+z &=2 \\ y-3 z &=1 \\ 2 x+y+5 z &=0 \end{aligned}\right. $$
4 step solution
Problem 29
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{aligned} 2 x^{2}-8 y^{3} &=19 \\ 4 x^{2}+16 y^{3} &=34 \end{aligned}\right. $$
5 step solution
Problem 29
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{2 x}{4 x^{2}+12 x+9} $$
7 step solution
Problem 29
\(21-48=\) Solve the system, or show that it has no solution. If the system has infinitely many solutions, express them in the ordered-pair form given in Example \(6 .\) $$ \left\\{\begin{array}{l}{x+2 y=7} \\ {5 x-y=2}\end{array}\right. $$
5 step solution
Problem 29
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \begin{array}{ll}{\text { (a) } G F} & {\text { (b) } G E}\end{array} $$
4 step solution
Problem 29
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} 2 x+3 y-z &=1 \\ x+2 y &=3 \\ x+3 y+z &=4 \end{aligned}\right. $$
5 step solution
Problem 30
Evaluate the determinant, using row or column operations whenever possible to simplify your work. $$ \left|\begin{array}{rrrr}{2} & {-1} & {6} & {4} \\ {7} & {2} & {-2} & {5} \\\ {4} & {-2} & {10} & {8} \\ {6} & {1} & {1} & {4}\end{array}\right| $$
6 step solution
Problem 30
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{array}{l}{y \geq x^{2}} \\ {y \leq 4} \\ {x \geq 0}\end{array}\right. $$
5 step solution
Problem 30
Determine whether the system of linear equations is inconsistent or dependent. If it is dependent, find the complete solution. $$ \left\\{\begin{array}{r}{x+3 z=3} \\ {2 x+y-2 z=5} \\ {-y+8 z=8}\end{array}\right. $$
5 step solution
Problem 30
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{aligned} x^{4}+y^{3} &=17 \\ 3 x^{4}+5 y^{3} &=53 \end{aligned}\right. $$
6 step solution
Problem 30
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{x-4}{(2 x-5)^{2}} $$
7 step solution
Problem 30
\(21-48=\) Solve the system, or show that it has no solution. If the system has infinitely many solutions, express them in the ordered-pair form given in Example \(6 .\) $$ \left\\{\begin{array}{l}{-4 x+12 y=0} \\ {12 x+4 y=160}\end{array}\right. $$
6 step solution
Problem 30
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \begin{array}{ll}{\text { (a) } B^{2}} & {\text { (b) } F^{2}}\end{array} $$
2 step solution
Problem 30
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} x-2 y-3 z &=5 \\ 2 x+y-z &=5 \\ 4 x-3 y-7 z &=5 \end{aligned}\right. $$
6 step solution
Problem 31
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{array}{l}{y<9-x^{2}} \\ {y \geq x+3}\end{array}\right. $$
5 step solution
Problem 31
Determine whether the system of linear equations is inconsistent or dependent. If it is dependent, find the complete solution. $$ \left\\{\begin{aligned} 2 x-3 y-9 z &=-5 \\ x +3 z=2\\\\-3 x+y-4 z &=-3 \end{aligned}\right. $$
7 step solution
Problem 31
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{array}{c}{\frac{2}{x}-\frac{3}{y}=1} \\\ {-\frac{4}{x}+\frac{7}{y}=1}\end{array}\right. $$
5 step solution
Problem 31
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{4 x^{2}-x-2}{x^{4}+2 x^{3}} $$
6 step solution
Problem 31
\(21-48=\) Solve the system, or show that it has no solution. If the system has infinitely many solutions, express them in the ordered-pair form given in Example \(6 .\) $$ \left\\{\begin{array}{l}{\frac{1}{2} x+\frac{1}{3} y=2} \\ {\frac{1}{5} x-\frac{2}{3} y=8}\end{array}\right. $$
7 step solution
Problem 31
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ A^{2} \quad \text { (b) } A^{3} $$
3 step solution
Problem 31
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} x+y-z &=0 \\ x+2 y-3 z &=-3 \\ 2 x+3 y-4 z &=-3 \end{aligned}\right. $$
5 step solution
Problem 32
Consider the system $$ \left\\{\begin{aligned} x+2 y+6 z &=5 \\\\-3 x-6 y+5 z &=8 \\ 2 x+6 y+9 z &=7 \end{aligned}\right. $$ (a) Verify that \(x=-1, y=0, z=1\) is a solution of the system. (b) Find the determinant of the coefficient matrix. (c) Without solving the system, determine whether there are any other solutions. (d) Can Cramer's Rule be used to solve this system? Why or why not?
5 step solution
Problem 32
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{aligned} y & \geq x^{2} \\ x+y & \geq 6 \end{aligned}\right. $$
5 step solution
Problem 32
Determine whether the system of linear equations is inconsistent or dependent. If it is dependent, find the complete solution. $$ \left\\{\begin{array}{rr}{x-2 y+5 z=} & {3} \\ {-2 x+6 y-11 z=} & {1} \\ {3 x-16 y-20 z=} & {-26}\end{array}\right. $$
5 step solution
Problem 32
\(19-32\) . Find all solutions of the system of equations. $$ \left\\{\begin{array}{l}{\frac{4}{x^{2}}+\frac{6}{y^{4}}=\frac{7}{2}} \\\ {\frac{1}{x^{2}}-\frac{2}{y^{4}}=0}\end{array}\right. $$
6 step solution
Problem 32
\(13-44=\) Find the partial fraction decomposition of the rational function. $$ \frac{x^{3}-2 x^{2}-4 x+3}{x^{4}} $$
6 step solution
Problem 32
The matrices \(A, B, C, D, E, F, G\) and \(H\) are defined as follows. $$ A=\left[\begin{array}{rr}{2} & {-5} \\ {0} & {7}\end{array}\right] \quad B=\left[\begin{array}{rrr}{3} & {\frac{1}{2}} & {5} \\ {1} & {-1} & {3}\end{array}\right] \quad C=\left[\begin{array}{rrr}{2} & {-\frac{5}{2}} & {0} \\ {0} & {2} & {-3}\end{array}\right] $$ $$ D=\left[\begin{array}{ll}{7} & {3}\end{array}\right] \quad E=\left[\begin{array}{l}{1} \\ {2} \\ {0}\end{array}\right] \quad F=\left[\begin{array}{lll}{1} & {0} & {0} \\ {0} & {1} & {0} \\ {0} & {0} & {1}\end{array}\right] $$ $$ G=\left[\begin{array}{rrr}{5} & {-3} & {10} \\ {6} & {1} & {0} \\ {-5} & {2} & {2}\end{array}\right] \quad H=\left[\begin{array}{rr}{3} & {1} \\ {2} & {-1}\end{array}\right] $$ Carry out the indicated algebraic operation, or explain why it cannot be performed. $$ \begin{array}{ll}{\text { (a) }(D A) B} & {\text { (b) } D(A B)}\end{array} $$
4 step solution
Problem 32
\(17-36\) . Find the complete solution of the linear system, or show that it is inconsistent. $$ \left\\{\begin{aligned} x-2 y+z &=3 \\ 2 x-5 y+6 z &=7 \\ 2 x-3 y-2 z &=5 \end{aligned}\right. $$
5 step solution
Problem 33
Use Cramer’s Rule to solve the system. $$ \left\\{\begin{aligned} 2 x-y &=-9 \\ x+2 y &=8 \end{aligned}\right. $$
6 step solution
Problem 33
21-46 . Graph the solution of the system of inequalities. Find the coordinates of all vertices, and determine whether the solution set is bounded. $$ \left\\{\begin{array}{r}{x^{2}+y^{2} \leq 4} \\ {x-y>0}\end{array}\right. $$
6 step solution