Skip to main content
Ch. 9 - First-Order Differential Equations
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077당신이 사용하는 게 아니라요?교과서 변경
9장, 문제 9.2.4

First-Order Linear Equations
Solve the differential equations in Exercises 1–14.


y' + (tanx)y = cos²x, -π/2 < x < π/2

검증된 단계별 안내
1
Identify the given differential equation as a first-order linear differential equation of the form \(y' + P(x)y = Q(x)\), where \(P(x) = \tan x\) and \(Q(x) = \cos^{2} x\).
Find the integrating factor \(\mu(x)\) using the formula \(\mu(x) = e^{\int P(x) \, dx} = e^{\int \tan x \, dx}\).
Compute the integral \(\int \tan x \, dx\) to determine the explicit form of the integrating factor \(\mu(x)\).
Multiply both sides of the original differential equation by the integrating factor \(\mu(x)\) to rewrite the left side as the derivative of the product \(\mu(x) y\).
Integrate both sides with respect to \(x\) to find \(\mu(x) y = \int \mu(x) Q(x) \, dx + C\), then solve for \(y\) by dividing both sides by \(\mu(x)\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
6m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

First-Order Linear Differential Equations

These are differential equations of the form y' + P(x)y = Q(x), where y' is the derivative of y with respect to x. They can be solved using an integrating factor, which simplifies the equation into an exact derivative, allowing integration to find the solution.
추천 영상:
07:39
Classifying Differential Equations

Integrating Factor Method

The integrating factor is a function, usually denoted μ(x) = e^(∫P(x)dx), used to multiply both sides of a linear differential equation. This transforms the left side into the derivative of (μ(x)y), making it easier to integrate and solve for y.
추천 영상:
07:33
Euler's Method

Trigonometric Functions in Differential Equations

Understanding the properties and integrals of trigonometric functions like tan(x) and cos²(x) is essential. These functions appear in P(x) and Q(x), and their integrals determine the integrating factor and the particular solution of the differential equation.
추천 영상:
6:04
Introduction to Trigonometric Functions