Is the First-Order Differential Equation Linear in Its Dependent Variable?

pupeye11
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Homework Statement



Determine whether the given first-order differential equation is linear in the indicated dependent variable by matching it with the first differential equations given in #7.


Homework Equations



#7 (sin \theta)y^{'''} - (cos \theta)y^{'} = 2

#10 (u)dv + (v+uv-ue^u)du = 0; in v; in u


The Attempt at a Solution



How can I do this problem when there is not a variable y in number 10?
 
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pupeye11 said:

Homework Statement



Determine whether the given first-order differential equation is linear in the indicated dependent variable by matching it with the first differential equations given in #7.


Homework Equations



#7 (sin \theta)y^{'''} - (cos \theta)y^{'} = 2
Underline added below.
pupeye11 said:
#10 (u)dv + (v+uv-ue^u)du = 0; in v; in u


The Attempt at a Solution



How can I do this problem when there is not a variable y in number 10?
There does not need to be a variable y. In #10 the question is in two parts: Is the differential equation linear in the indicated dependent variable - in v, and then in u. For the first part, assume that v is the dependent variable; for the second part, assume that u is the independent variable.
 
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