Solving differential equations

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SUMMARY

The differential equation f''(x) = sin(x) with initial conditions f(0) = 0 and f'(0) = 1 is solved correctly as f(x) = -sin(x) + 2x. The solution process involves integrating the second derivative to find the first derivative, applying the initial conditions to determine constants, and integrating again to find the original function. The constants C1 and C2 are calculated as 2 and 0, respectively, confirming the solution is accurate.

PREREQUISITES
  • Understanding of differential equations
  • Knowledge of integration techniques
  • Familiarity with initial value problems
  • Basic trigonometric functions and their properties
NEXT STEPS
  • Study methods for solving higher-order differential equations
  • Learn about Laplace transforms for differential equations
  • Explore numerical methods for approximating solutions to differential equations
  • Investigate applications of differential equations in physics and engineering
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Students studying calculus, mathematicians, and engineers who need to solve differential equations and apply initial conditions in their work.

chapsticks
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Homework Statement




Solve the following differential equation:

f"(x)=sinx

x(0)=0, x'(0)=1

Homework Equations



x(0)=0, x'(0)=1

The Attempt at a Solution




f"(x)=sin(x)
integrate,
f'(x)=-cos(x)+C1
f'(0)=-cos(0)+C1=1 => C1=2
C1=2
f'(x)=-cos(x)+2
f(x)=-sin(x)+2x+C2
f(0)=-sin(0)+C2=0 => C2=0

=>
f(x)=-sin(x)+2x
 
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It is correct.

ehild
 
chapsticks said:

Homework Statement




Solve the following differential equation:

f"(x)=sinx

x(0)=0, x'(0)=1
Minor point, but this should be f(0) = 0, f'(0) = 1.
chapsticks said:

Homework Equations



x(0)=0, x'(0)=1

The Attempt at a Solution




f"(x)=sin(x)
integrate,
f'(x)=-cos(x)+C1
f'(0)=-cos(0)+C1=1 => C1=2
C1=2
f'(x)=-cos(x)+2
f(x)=-sin(x)+2x+C2
f(0)=-sin(0)+C2=0 => C2=0

=>
f(x)=-sin(x)+2x
What's your question?
 

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