# 7.8 - Home> My Assignments> Section 7.8(Homework About...

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Home > My Assignments > Section 7.8 (Homework) About this Assignment SMALL BRIAN DIXON MA 241, section 009, Fall 2005 Instructor: Drew Pasteur North Carolina State University Due: Thursday, October 27, 2005 11:06 PM EDT Description Nonhomogeneous Current Score: 14.5 out of 16.5 Linear Equations Question Score pts 1 1/1 2 0.5/0.5 3 2/2 3.5/3.5 Viewing: Last Response View: All Responses Notes subs 1/20 1/20 1/20 1. [SCalcCC2 7.8.02.] Solve the differential equation using the method of undetermined coefficients. y'' + 9y = e3x (a) Find the auxiliary equation using the variable r. r^2+9 [r^2+9] = 0 (b) Determine the complementary solution. (_) (_) (_) (_) none of these (o) (o) (_) (_) (_) (_) (c) Find the general solution. y(x) = yc(x) + (1/18)*exp(3x) [(1/18)*exp(3x)] pts 1 1/1 2 0.5/0.5 3 2/2 3.5/3.5 subs 1/20 1/20 1/20 2. [SCalcCC2 7.8.06.] Solve the differential equation using the method of undetermined coefficients. y'' + 2y' + y = xe-x (a) Find the auxiliary equation using the variable r. r^2 + 2r + 1 [r^2 + 2r + 1] = 0 Viewing: Last Response View: All Responses Notes (b) Determine the complementary solution. (_) (_) none of these (_) (_) (_) (_) (_) (_) (o) (o) (c) Find the general solution. y(x) = yc(x) + (1/6)*x^3*exp(-x) [(1/6)*x^3*exp(-x)] pts subs 1 3/3 2/20 3/3 Viewing: Last Response View: All Responses Notes pts subs 1 3/3 2/20 3/3 Viewing: Last Response View: All Responses Notes pts 1 1/1 2 0.5/0.5 3 0/2 1.5/3.5 3. [SCalcCC2 7.8.08.] Solve the initial-value problem using the method of undetermined coefficients. y'' - 4y = excos(x) , y(0) = 1 , y'(0) = 2 y(x) = (9/8)*exp(2x) + (3/40)*exp(-2x) + exp(x)*(-1/5 cos(x) + 1/10 sin(x)) [(9/8)*exp(2x) + (3/40)*exp(-2x) + exp(x)*(-1/5 cos(x) + 1/10 sin(x))] 4. [SCalcCC2 7.8.10.] Solve the initial-value problem using the method of undetermined coefficients. y'' + y' - 2y = x + sin(2x) , y(0) = 1 , y'(0) = 0 y(x) = (17/15)*exp(x) + (1/6)*exp(-2x) - 1/2*x - 1/4 - 1/20 cos(2x) - 3/20 sin(2x) [(17/15)*exp(x) + (1/6)*exp(-2x) - 1/2*x - 1/4 - 1/20 cos(2x) - 3/20 sin(2x)] 5. [SCalcCC2 7.8.18.] Solve the differential equation using the method of undetermined coefficients or variation of parameters. y'' - 3y' + 2y = sin(x) (a) Find the auxiliary equation using the variable r. r^2 - 3r + 2 [r^2 - 3r + 2] = 0 subs 1/20 3/20 1/20 Viewing: Last Response View: All Responses Notes (b) Determine the complementary solution. (_) (_) (_) (_) (o) (o) (_) (_) none of these (_) (_) (c) Find the general solution. y(x) = yc(x) + (1/6)*exp(1.5x) (1/10)sin(x)] [(3/10)cos(x) + Home My Assignments ...
View Full Document

## This note was uploaded on 10/21/2009 for the course MATH MA241 taught by Professor Hubbard during the Spring '09 term at N.C. Central.

Ask a homework question - tutors are online