7.42 problem 42

7.42.1 Solving as quadrature ode
7.42.2 Maple step by step solution

Internal problem ID [13463]
Internal file name [OUTPUT/12635_Friday_February_16_2024_12_01_05_AM_2144882/index.tex]

Book: Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section: Chapter 8. Review exercises for part of part II. page 143
Problem number: 42.
ODE order: 1.
ODE degree: 1.

The type(s) of ODE detected by this program : "quadrature"

Maple gives the following as the ode type

[_quadrature]

\[ \boxed {y^{\prime }=\sin \left (x \right )-2 x} \]

7.42.1 Solving as quadrature ode

Integrating both sides gives \begin {align*} y &= \int { \sin \left (x \right )-2 x\,\mathop {\mathrm {d}x}}\\ &= -x^{2}-\cos \left (x \right )+c_{1} \end {align*}

Summary

The solution(s) found are the following \begin{align*} \tag{1} y &= -x^{2}-\cos \left (x \right )+c_{1} \\ \end{align*}

Figure 441: Slope field plot

Verification of solutions

\[ y = -x^{2}-\cos \left (x \right )+c_{1} \] Verified OK.

7.42.2 Maple step by step solution

\[ \begin {array}{lll} & {} & \textrm {Let's solve}\hspace {3pt} \\ {} & {} & y^{\prime }=\sin \left (x \right )-2 x \\ \bullet & {} & \textrm {Highest derivative means the order of the ODE is}\hspace {3pt} 1 \\ {} & {} & y^{\prime } \\ \bullet & {} & \textrm {Integrate both sides with respect to}\hspace {3pt} x \\ {} & {} & \int y^{\prime }d x =\int \left (\sin \left (x \right )-2 x \right )d x +c_{1} \\ \bullet & {} & \textrm {Evaluate integral}\hspace {3pt} \\ {} & {} & y=-x^{2}-\cos \left (x \right )+c_{1} \\ \bullet & {} & \textrm {Solve for}\hspace {3pt} y \\ {} & {} & y=-x^{2}-\cos \left (x \right )+c_{1} \end {array} \]

Maple trace

`Methods for first order ODEs: 
--- Trying classification methods --- 
trying a quadrature 
<- quadrature successful`
 

Solution by Maple

Time used: 0.0 (sec). Leaf size: 15

dsolve(diff(y(x),x)+2*x=sin(x),y(x), singsol=all)
 

\[ y \left (x \right ) = -x^{2}-\cos \left (x \right )+c_{1} \]

Solution by Mathematica

Time used: 0.009 (sec). Leaf size: 17

DSolve[y'[x]+2*x==Sin[x],y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to -x^2-\cos (x)+c_1 \]