Respuesta :
Answer:
[tex]\displaystyle y(2) = e^3[/tex]
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
- Left to Right
Equality Properties
Algebra I
- Functions
- Function Notation
- Exponential Rule [Multiplying]: [tex]\displaystyle b^m \cdot b^n = b^{m + n}[/tex]
Algebra II
- Natural Logarithms ln and Euler's number e
Calculus
Derivatives
Derivative Notation
Basic Power Rule:
- f(x) = cxⁿ
- f’(x) = c·nxⁿ⁻¹
Slope Fields
- Separation of Variables
- Solving Differentials
Integrals
- Antiderivatives
Integration Constant C
Integration Rule [Reverse Power Rule]: [tex]\displaystyle \int {x^n} \, dx = \frac{x^{n + 1}}{n + 1} + C[/tex]
Integration Property [Multiplied Constant]: [tex]\displaystyle \int {cf(x)} \, dx = c \int {f(x)} \, dx[/tex]
Integration Property [Addition/Subtraction]: [tex]\displaystyle \int {[f(x) \pm g(x)]} \, dx = \int {f(x)} \, dx \pm \int {g(x)} \, dx[/tex]
Logarithmic Integration: [tex]\displaystyle \int {\frac{1}{u}} \, dx = ln|u| + C[/tex]
Explanation:
*Note:
When solving differential equations in slope fields, disregard the integration constant C for variable y.
Step 1: Define
[tex]\displaystyle \frac{dy}{dx} = (2x - 1)y[/tex]
[tex]\displaystyle y(1) = e[/tex]
Step 2: Rewrite
Separation of Variables. Get differential equation to a form where we can integrate both sides and rewrite Leibniz Notation.
- [Separation of Variables] Rewrite Leibniz Notation: [tex]\displaystyle dy = (2x - 1)y \ dx[/tex]
- [Separation of Variables] Isolate y's together: [tex]\displaystyle \frac{1}{y} \ dy = (2x - 1) \ dx[/tex]
Step 3: Find General Solution
- [Differential] Integrate both sides: [tex]\displaystyle \int {\frac{1}{y}} \, dy = \int {(2x - 1)} \, dx[/tex]
- [dy Integral] Integrate [Logarithmic Integration]: [tex]\displaystyle ln|y| = \int {(2x - 1)} \, dx[/tex]
- [dx Integral] Rewrite [Integration Property - Addition/Subtraction]: [tex]\displaystyle ln|y| = \int {2x} \, dx - \int {} \, dx[/tex]
- [1st dx Integral] Rewrite [Integration Property - Multiplied Constant]: [tex]\displaystyle ln|y| = 2\int {x} \, dx - \int {} \, dx[/tex]
- [dx Integrals] Integrate [Integration Rule - Reverse Power Rule]: [tex]\displaystyle ln|y| = 2(\frac{x^2}{2}) - x + C[/tex]
- Simplify: [tex]\displaystyle ln|y| = x^2 - x + C[/tex]
- [Equality Property] e both sides: [tex]\displaystyle e^\bigg{ln|y|} = e^\bigg{x^2 - x + C}[/tex]
- Simplify: [tex]\displaystyle |y| = Ce^\bigg{x^2 - x}[/tex]
- Rewrite: [tex]\displaystyle y = \pm Ce^\bigg{x^2 - x}[/tex]
General Solution: [tex]\displaystyle y = \pm Ce^\bigg{x^2 - x}[/tex]
Step 4: Find Particular Solution
- Substitute in function values [General Solution]: [tex]\displaystyle e = \pm Ce^\bigg{1^2 - 1}[/tex]
- Simplify: [tex]\displaystyle e = \pm C[/tex]
- Rewrite: [tex]\displaystyle C = e[/tex]
- Substitute in C [General Solution]: [tex]\displaystyle y = e \bigg( e^\bigg{x^2 - x} \bigg)[/tex]
- Simplify [Exponential Rule - Multiplying]: [tex]\displaystyle y = e^\bigg{x^2 - x + 1}[/tex]
Particular Solution: [tex]\displaystyle y = e^\bigg{x^2 - x + 1}[/tex]
Step 5: Solve
- Substitute in x [Particular Solution]: [tex]\displaystyle y(2) = e^\bigg{2^2 - 2 + 1}[/tex]
- Simplify: [tex]\displaystyle y(2) = e^3[/tex]
∴ our final answer is [tex]\displaystyle y(2) = e^3[/tex].
Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Differentials and Slope Fields
Book: College Calculus 10e