How to find two constants in an equation

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SUMMARY

The discussion focuses on solving an initial value problem involving a two-parameter family of functions defined by the equation x = c1*cos(t) + c2*sin(t), with the conditions x'' + x = 0, x(pi/6) = 1/2, and x'(pi/6) = 0. The user successfully derived the first equation, sqrt(3)*c1/2 + c2/2 = 1/2, but needed guidance on obtaining a second equation to solve for the constants c1 and c2. The solution involves taking the first derivative of the function and applying the second initial condition to generate a system of linear equations.

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Homework Statement



i'm trying to find two constants in the same equation. its an initial value problem

there's a two parameter family x=c1cost+c2sint with initial conditions x''+x=0, x(pi/6)=1/2, and x'(pi/6)=0

so I'm trying to find c1, and i equate the problem to 1/2 and subsitute the t's for pi/6, so it looks like

1/2=c1cos(pi/6)+c2sin(pi/6)

which of course equals sqrt(3)c1/2 + c2/2

but how do i get the values of c1 and c2? I've tried everything and i need them to find a solution

Homework Equations





The Attempt at a Solution

 
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well, you already found one relation sqrt(3)c1/2 + c2/2=1/2, to find another relation,

take the first derivative of x=c1cost+c2sint, and apply the second contidion that you are given x'(pi/6)=0

so you'll get two lin. eq in two unknowns, c1,c2, and u should be able to solve it.
 

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