L1 Domain, Range, and Interval Notation - Practice 1
Completion requirements
Unit 1A
Precalculus
Lesson 1: Domain, Range, and Interval Notation
Practice
Once you feel confident with domain, range and set builder notation, click on the Practice tab and complete problems 1 and 2. Check your answers by going to the Solutions tab.
Instructions: Click the Download File button to download a printable PDF of the questions. Answer each of the following practice questions on a separate piece of paper. Step by step solutions are provided under the Solutions tab. You will learn the material more thoroughly if you complete the questions before checking the answers.
Instructions: Click the Download File button to download a printable PDF of the questions. Answer each of the following practice questions on a separate piece of paper. Step by step solutions are provided under the Solutions tab. You will learn the material more thoroughly if you complete the questions before checking the answers.
1.
Determine the domain and range of the function «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»h«/mi»«mi mathvariant=¨normal¨»(«/mi»«mi»x«/mi»«mi mathvariant=¨normal¨»)«/mi»«mo»=«/mo»«mfrac»«msqrt»«mi»x«/mi»«mo»+«/mo»«mn»2«/mn»«/msqrt»«mrow»«msup»«mi»x«/mi»«mn»2«/mn»«/msup»«mo»+«/mo»«mn»2«/mn»«mi»x«/mi»«mo»§#8722;«/mo»«mn»3«/mn»«/mrow»«/mfrac»«/mrow»«/mstyle»«/math».
Express your answer in set builder notation.
2.
Determine the domain and range of the function «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»y«/mi»«mo»=«/mo»«mi»g«/mi»«mfenced»«mi»t«/mi»«/mfenced»«/mrow»«/mstyle»«/math» graphed
below.
1.
Determine the domain and range of the function «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»h«/mi»«mi mathvariant=¨normal¨»(«/mi»«mi»x«/mi»«mi mathvariant=¨normal¨»)«/mi»«mo»=«/mo»«mfrac»«msqrt»«mi»x«/mi»«mo»+«/mo»«mn»2«/mn»«/msqrt»«mrow»«msup»«mi»x«/mi»«mn»2«/mn»«/msup»«mo»+«/mo»«mn»2«/mn»«mi»x«/mi»«mo»§#8722;«/mo»«mn»3«/mn»«/mrow»«/mfrac»«/mrow»«/mstyle»«/math».
Express your answer in set builder notation.
The function is undefined when the denominator is equal to zero. Set the denominator equal to zero and then solve for the restrictions on «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle
mathsize=¨14px¨»«mi»x«/mi»«/mstyle»«/math».
Therefore, the restrictions are «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»x«/mi»«mo»§#8800;«/mo»«mo»§#8722;«/mo»«mn»3«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»§#8800;«/mo»«mn»1«/mn»«/mrow»«/mstyle»«/math».
The radical in the numerator is only defined for positive values, so «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»x«/mi»«mo»+«/mo»«mn»2«/mn»«mo»§#8805;«/mo»«mn»0«/mn»«/mrow»«/mstyle»«/math». As such, «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»x«/mi»«mo»§#8805;«/mo»«mo»§#8722;«/mo»«mn»2«/mn»«/mrow»«/mstyle»«/math».
To determine the domain, combine all of the restrictions. The domain, in set builder notation, is «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»x«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi»x«/mi»«mo»§#8805;«/mo»«mo»§#8722;«/mo»«mn»2«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»§#8800;«/mo»«mn»1«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
Graph the function to determine the range.
From the graph, it can be seen there are no restricted function values. Therefore, «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»y«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi mathvariant=¨normal¨»y«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
«math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mtable columnalign=¨left¨»«mtr»«mtd»«msup»«mi»x«/mi»«mn»2«/mn»«/msup»«mo»+«/mo»«mn»2«/mn»«mi»x«/mi»«mo»§#8722;«/mo»«mn»3«/mn»«mo»=«/mo»«mn»0«/mn»«/mtd»«/mtr»«mtr»«mtd»«mi
mathvariant=¨normal¨»(«/mi»«mi»x«/mi»«mo»+«/mo»«mn»3«/mn»«mi»)(«/mi»«mi»x«/mi»«mo»§#8722;«/mo»«mn»1«/mn»«mi mathvariant=¨normal¨»)«/mi»«mo»=«/mo»«mn»0«/mn»«/mtd»«/mtr»«mtr»«mtd»«mi»x«/mi»«mo»=«/mo»«mo»§#8722;«/mo»«mn»3«/mn»«mi
mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»=«/mo»«mn»1«/mn»«/mtd»«/mtr»«/mtable»«/mstyle»«/math»
| To solve for «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mi»x«/mi»«/mstyle»«/math», factor the quadratic equation. |
The radical in the numerator is only defined for positive values, so «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»x«/mi»«mo»+«/mo»«mn»2«/mn»«mo»§#8805;«/mo»«mn»0«/mn»«/mrow»«/mstyle»«/math». As such, «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»x«/mi»«mo»§#8805;«/mo»«mo»§#8722;«/mo»«mn»2«/mn»«/mrow»«/mstyle»«/math».
To determine the domain, combine all of the restrictions. The domain, in set builder notation, is «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»x«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi»x«/mi»«mo»§#8805;«/mo»«mo»§#8722;«/mo»«mn»2«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»§#8800;«/mo»«mn»1«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»x«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
| Notice «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mi»x«/mi»«mo»§#8800;«/mo»«mo»-«/mo»«mn»3«/mn»«/mstyle»«/math» is not included in set builder notation. Since «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mo»-«/mo»«mn»3«/mn»«/mstyle»«/math» is less than «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mo»-«/mo»«mn»2«/mn»«mo»,«/mo»«/mstyle»«/math» it is not necessary to include this restriction of «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mi»x«/mi»«/mstyle»«/math» in the domain. |
From the graph, it can be seen there are no restricted function values. Therefore, «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»y«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi mathvariant=¨normal¨»y«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
2.
Determine the domain and range of the function «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»y«/mi»«mo»=«/mo»«mi»g«/mi»«mfenced»«mi»t«/mi»«/mfenced»«/mrow»«/mstyle»«/math»
graphed below.
The only restriction on the domain results from the vertical asymptote at «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»t«/mi»«mo»=«/mo»«mn»2«/mn»«/mrow»«/mstyle»«/math».
The domain is «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»t«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi»t«/mi»«mo»§#8800;«/mo»«mn»2«/mn»«mi
mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»t«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
From the graph, it can be seen the function values are restricted to «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»y«/mi»«mo»§#8804;«/mo»«mn»2«/mn»«/mrow»«/mstyle»«/math» and «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mi»y«/mi»«mo»§#8805;«/mo»«mn»6«/mn»«/mstyle»«/math». The range is «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»y«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi»y«/mi»«mo»§#8804;«/mo»«mn»2«/mn»«mi mathvariant=¨normal¨» «/mi»«mo»§#160;«/mo»«mi»and«/mi»«mi mathvariant=¨normal¨» «/mi»«mo»§#160;«/mo»«mi»y«/mi»«mo»§#8805;«/mo»«mn»6«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»y«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».
From the graph, it can be seen the function values are restricted to «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mrow»«mi»y«/mi»«mo»§#8804;«/mo»«mn»2«/mn»«/mrow»«/mstyle»«/math» and «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mi»y«/mi»«mo»§#8805;«/mo»«mn»6«/mn»«/mstyle»«/math». The range is «math style=¨font-family:Verdana¨ xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mstyle mathsize=¨14px¨»«mfenced open=¨{¨ close=¨}¨»«mrow»«mi»y«/mi»«mi mathvariant=¨normal¨»|«/mi»«mi»y«/mi»«mo»§#8804;«/mo»«mn»2«/mn»«mi mathvariant=¨normal¨» «/mi»«mo»§#160;«/mo»«mi»and«/mi»«mi mathvariant=¨normal¨» «/mi»«mo»§#160;«/mo»«mi»y«/mi»«mo»§#8805;«/mo»«mn»6«/mn»«mi mathvariant=¨normal¨»,«/mi»«mo»§#160;«/mo»«mi»y«/mi»«mo»§#8712;«/mo»«mi mathvariant=¨normal¨»R«/mi»«/mrow»«/mfenced»«/mstyle»«/math».