Common Core: High School - Functions : Express Exponential Models as Logarithmic Solutions: CCSS.Math.Content.HSF-LE.A.4

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Example Questions

Example Question #1 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle e^{x-4}+2=10\) 

Possible Answers:

\(\displaystyle x=\frac{\ln 8}{2}\)

\(\displaystyle x=\ln 8+4\)

\(\displaystyle x={\ln 4}\)

\(\displaystyle x=\ln 8-4\)

\(\displaystyle x=\frac{\ln 8}{4}\)

Correct answer:

\(\displaystyle x=\ln 8+4\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle e^{x-4}+2=10\)

Subtract two from both sides.

\(\displaystyle \\e^{x-4}+2-2=10-2 \\e^{x-4}=8\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^{x-4}=8 \\ \ln e^{x-4}=\ln 8\\ x-4=\ln 8\\x=\ln 8+4\)

Example Question #1 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle e^{x-4}+1=5\)

Possible Answers:

\(\displaystyle x=\ln4-4\)

\(\displaystyle x=\ln4-1\)

\(\displaystyle x=\ln1+4\)

\(\displaystyle x=\ln4+4\)

\(\displaystyle x=\ln4+1\)

Correct answer:

\(\displaystyle x=\ln4+4\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle e^{x-4}+1=5\)

Subtract one from both sides.

\(\displaystyle \\e^{x-4}+1-1=5-1 \\e^{x-4}=4\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^{x-4}=4 \\ \ln e^{x-4}=\ln 4\\ x-4=\ln 4\\x=\ln 4+4\)

Example Question #3 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle 2e^{x}+1=5\)

Possible Answers:

\(\displaystyle x=\ln1\)

\(\displaystyle x=\ln2\)

\(\displaystyle x=\sqrt{\ln4}\)

\(\displaystyle x=\ln4\)

\(\displaystyle x=\sqrt{\ln2}\)

Correct answer:

\(\displaystyle x=\ln2\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle 2e^{x}+1=5\)

Subtract one from both sides.

\(\displaystyle \\2e^{x}+1-1=5-1 \\2e^{x}=4\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\2e^x=4 \\e^x=\frac{4}{2} \\ \\e^x=2 \\ \ln e^x=\ln2 \\x=\ln 2\)

Example Question #2 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle 2e^{x}+5=17\)

Possible Answers:

\(\displaystyle x=\ln6+2\)

\(\displaystyle x=\ln4-2\)

\(\displaystyle x=\ln6\)

\(\displaystyle x=\ln4\)

\(\displaystyle x=\ln12-2\)

Correct answer:

\(\displaystyle x=\ln6\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle 2e^{x}+5=17\)

Subtract five from both sides and then divide by two.

\(\displaystyle \\2e^{x}+5-5=17-5\\2e^{x}=12\\e^x=6\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^x=6 \\ \ln e^x=\ln6 \\x=\ln 6\)

Example Question #1 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle 4e^{x}+5=17\)

Possible Answers:

\(\displaystyle x=\ln6\)

\(\displaystyle x=1\)

\(\displaystyle x=3\)

\(\displaystyle x=-\ln3\)

\(\displaystyle x=\ln3\)

Correct answer:

\(\displaystyle x=\ln3\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle 4e^{x}+5=17\)

Subtract five from both sides and then divide by four.

\(\displaystyle \\4e^{x}+5-5=17-5\\4e^{x}=12\\e^x=3\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^x=3 \\ \ln e^x=\ln3 \\x=\ln 3\)

Example Question #6 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle 4e^{x}+5=13\)

Possible Answers:

\(\displaystyle x=\ln2-1\)

\(\displaystyle x=\ln1\)

\(\displaystyle x=\ln2\)

\(\displaystyle x=2\)

\(\displaystyle x=e^2\)

Correct answer:

\(\displaystyle x=\ln2\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle 4e^{x}+5=13\)

Subtract five from both sides and then divide by four.

\(\displaystyle \\4e^{x}+5-5=13-5\\4e^{x}=8\\e^x=2\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^x=2 \\ \ln e^x=\ln2 \\x=\ln 2\)

Example Question #5 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle 4e^{x}-6=12\)

Possible Answers:

\(\displaystyle x=\ln \frac{9}{2}\)

\(\displaystyle x=\ln\frac{2}{9}\)

\(\displaystyle x=-\ln18\)

\(\displaystyle x=\ln2+18\)

\(\displaystyle x=\ln18-2\)

Correct answer:

\(\displaystyle x=\ln \frac{9}{2}\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle 4e^{x}-6=12\)

Add six from both sides and then divide by four.

\(\displaystyle \\4e^{x}-6+6=12+6\\4e^{x}=18\\\\e^x=\frac{9}{2}\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^x=\frac{9}{2} \\\\ \ln e^x=\ln\frac{9}{2} \\x=\ln \frac{9}{2}\)

Example Question #1 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle e^{x-4}-2=10\)

Possible Answers:

\(\displaystyle x=\ln6-2\)

\(\displaystyle x=\ln4\)

\(\displaystyle x=\ln12+4\)

\(\displaystyle x=\ln6+2\)

\(\displaystyle x=\ln12-4\)

Correct answer:

\(\displaystyle x=\ln12+4\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle e^{x-4}-2=10\)

Add two from both sides.

\(\displaystyle \\e^{x-4}-2+2=10+2 \\e^{x-4}=12\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^{x-4}=12 \\ \ln e^{x-4}=\ln 12\\ x-4=\ln 12\\x=\ln 12+4\)

Example Question #1 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle e^{x-4}-1=5\)

Possible Answers:

\(\displaystyle x=\ln 6-4\)

\(\displaystyle x=\ln 6-2\)

\(\displaystyle x=\ln 6+2\)

\(\displaystyle x=\ln 6\)

\(\displaystyle x=\ln 6+4\)

Correct answer:

\(\displaystyle x=\ln 6+4\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle e^{x-4}-1=5\)

Add one from both sides.

\(\displaystyle \\e^{x-4}-1+1=5+1 \\e^{x-4}=6\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^{x-4}=6 \\ \ln e^{x-4}=\ln 6\\ x-4=\ln 6\\x=\ln 6+4\)

Example Question #10 : Express Exponential Models As Logarithmic Solutions: Ccss.Math.Content.Hsf Le.A.4

Solve for \(\displaystyle x\) using rules of logarithmic functions.

\(\displaystyle e^{x-4}-1=1\)

Possible Answers:

\(\displaystyle x=\ln 2-4\)

\(\displaystyle x=\ln 2+2\)

\(\displaystyle x=\ln 2+4\)

\(\displaystyle x=\ln 2-2\)

\(\displaystyle x=\ln 2+1\)

Correct answer:

\(\displaystyle x=\ln 2+4\)

Explanation:

This question is testing one's ability to understand logarithmic rules and apply them in order to solve a function.

For the purpose of Common Core Standards, "For exponential models, express as a logarithm the solution to ab^(ct) = d where ac, and dare numbers and the base b is 2, 10, or e; evaluate the logarithm using technology." falls within the Cluster A of "Construct and compare linear, quadratic, and exponential models and solve problems" concept (CCSS.MATH.CONTENT.HSF-LE.A.4). 

Knowing the standard and the concept for which it relates to, we can now do the step-by-step process to solve the problem in question.

Step 1: Use algebraic operations to manipulate the function and isolate the \(\displaystyle x\) value on one side of the equation.

\(\displaystyle e^{x-4}-1=1\)

Add one from both sides.

\(\displaystyle \\e^{x-4}-1+1=1+1 \\e^{x-4}=2\)

Step 2: Identify logarithmic rules.

Recall that \(\displaystyle \ln e=1\)

Step 3: Apply logarithmic rules to solve for \(\displaystyle x\)

\(\displaystyle \\e^{x-4}=2 \\ \ln e^{x-4}=\ln 2\\ x-4=\ln 2\\x=\ln 2+4\)

All Common Core: High School - Functions Resources

6 Diagnostic Tests 82 Practice Tests Question of the Day Flashcards Learn by Concept
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