Theoretical question on solutions

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we have y'=f(x)y+g(x) when f and g are continues on (a,b).
and there is a point x_0 for which g(x_0) differs zero.suppose that u_1 and u_2 are
solution to the equation on (a,b) .and if for some c,d d*u_1+c*u_2 is also a solution
thn we cn conclude that : (we need to choose one of the options)
A. c or d is zero
B. c=1-d
C. c^2+d^2=1
D.if u_1 and u_2 are
solution to the equation then d*u_1+c*u_2 is also a solution


i only know that on (a,b) there could be a single solution for the initial condition.
thats my theoretical knowledge on the subject
 
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nhrock3 said:
we have y'=f(x)y+g(x) when f and g are continues on (a,b).
and there is a point x_0 for which g(x_0) differs zero.suppose that u_1 and u_2 are
solution to the equation on (a,b) .and if for some c,d d*u_1+c*u_2 is also a solution
thn we cn conclude that : (we need to choose one of the options)
A. c or d is zero
B. c=1-d
C. c^2+d^2=1
D.if u_1 and u_2 are
solution to the equation then d*u_1+c*u_2 is also a solution


i only know that on (a,b) there could be a single solution for the initial condition.
thats my theoretical knowledge on the subject

Start working with your given information. For example, since u1 and u2 are solutions to the diff. equation, then
u1'(x) = f(x)u1(x) + g(x), and
u2'(x) = f(x)u2(x) + g(x).

It also says that for some c and d, cu1 + du2 is a solution. What does that mean in terms of the given differential equation?
 
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