Semester Exam Self-Assessment Study Notes: Unit 5 Rational Exponents & Radical Functions
Semester Exam Self-Assessment Overview
This document serves as a study guide and self-assessment for the Semester Exam, completed by student Carson Jackson.
Task: Solve identifying problems without assistance and mark confidence levels for each problem type.
Due Date: Monday.
Subject Area: Unit 5 - Rational Exponents & Radical Functions.
Problem 1: Rational Exponents to Radicals
Problem Statement: Rewrite 1643 using radicals, then evaluate.
Concept: The rational exponent rule states anm=(na)m or nam.
Evaluation Process:
* Step 1: Convert to radical form: (416)3
* Step 2: Evaluate the fourth root: Since 2×2×2×2=16, 416=2
* Step 3: Cube the result: 23=8
Student Status: Confident.
Problem 2: Solving Power Equations
Problem Statement: Solve the equation x23=9
Theoretical Approach: To solve for x, raise both sides of the equation to the reciprocal of the power, which is 32.
* Equation: (x23)32=932
* Simplified: x=(39)2
Student Scratch Notes:
* "X-9"
* "19-3"
* "4=3" (Note: This appears to be a transcription error in the student's scratch work)
* "33 27"
Student Status: Unsure.
Problem 3: Simplifying Radical Expressions
Problem Statement: Simplify completely 72x4
Simplification Process:
* Factor the number into a perfect square and a remainder: 72=36×2
* Simplify the square root of the perfect square: 62
* Simplify the variable component: x4=x2
* Combine results: 6x22
Student Work Details:
* Step-by-step noted: "36⋅2=62"
* Variable result: "x2"
* Final output listed: "6x22"
Student Status: Confident.
Problem 4: Product Power Rule and Rational Exponents
Problem Statement: Simplify and write with positive rational exponents: (8x3)31
Rule: The Power of a Product Rule applies (ab)n=anbn.
Simplification Steps:
* Apply exponent to the coefficient: 831=38=2
* Apply exponent to the variable: (x3)31=x3×31=x1
* Result: 2x
Student Commentary: "I have no clue"
Student Status: Lost.
Problem 5: Square Root Function Characteristics
Problem Statement: Describe the domain, range, and starting point of f(x)=x−4
Critical Values:
* Domain: Setting the radicand to greater than or equal to zero (x−4≥0) yields x≥4.
* Starting Point: Determined by the horizontal shift of 4 and no vertical shift, identified as (4,0).
* Range: Since the function is a positive square root with no vertical shift, y≥0.
Student Annotations:
* Domain identified as "D=x≥4"
* Starting point identified as "SP(4,0)"
Student Status: Confident.
Problem 6: Transformations of Square Root Functions
Problem Statement: Describe the transformations from y=x to y=−2x+1+3
Identified Transformations:
1. Reflection: The negative sign in front of the 2 indicates a reflection across the x-axis.
2. Vertical Stretch: The coefficient 2 indicates a Vertical Stretch (VS) by a factor of 2.
3. Horizontal Shift: The "x+1" inside the radical indicates a shift Left by 1 (L1).
4. Vertical Shift: The "+3" indicates a shift Up by 3.
Problem Statement: Describe the domain and end behavior of f(x)=3x−5
Function Properties:
* Domain (D): For cube root functions, the domain is the set of all real numbers (R).
* Range (R): The range is also all real numbers (R).
* End Behavior:
* As x→∞, f(x)→∞
* As x→−∞, f(x)→−∞
Student Annotations:
* Domain: "D:R"
* End behavior noted as: "x→∞,f(x)→∞" and "x→−∞,f(x)→−∞"
Student Status: Confident.
Problem 8: Cube Root Transformations
Problem Statement: Describe the transformations from y=3x to y=3x+2−1
Identified Transformations:
1. Horizontal Shift: The "x+2" indicates a shift to the left by 2.
2. Vertical Shift: The "−1" indicates a shift down by 1.
Student Abbreviations Used:
* "vs left x2" (Note: This uses "vs" likely standing for "vertical shift" incorrectly or simply a general notation for shift)
* "down x1"
Student Status: Confident.
Problem 9: Solving and Verifying Radical Equations
Problem Statement: Solve and check: 2x−1=x−1
Solving Process:
* Step 1: Square both sides of the equation to eliminate the radical.
* (2x−1)2=(x−1)2
* 2x−1=x2−2x+1
* Step 2: Move all terms to one side to set the quadratic equation to zero.
* x2−4x+2=0
* Step 3: Solve using the Quadratic Formula: x=2a−b±b2−4ac
* x=2(1)4±(−4)2−4(1)(2)
* x=24±16−8=24±8=24±22
* x=2±2