If P(x) and Q(y) are arbitrary functions of x and y respectively, then...
Proof : The given differential equation is
P(x)dx+Q(y)dy = 0 ...(i)
Comparing it with
Mdx + Ndy = 0 ...(ii)
∴ M = P(x) and N = Q(y)
is always satisfied.
⇒ D.E. (i) is always exact.
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If P(x) and Q(y) are arbitrary functions of x and y respectively, then...
The given differential equation is P(x)dx + Q(y)dy = 0, where P(x) and Q(y) are arbitrary functions of x and y respectively. We are asked to determine if this differential equation is exact or not.
To determine if a differential equation is exact, we need to check if it satisfies the condition:
∂(M)/∂(y) = ∂(N)/∂(x)
where M = P(x) and N = Q(y).
Let's calculate the partial derivatives:
∂(M)/∂(y) = 0 (since M = P(x) does not involve y)
∂(N)/∂(x) = 0 (since N = Q(y) does not involve x)
Since the partial derivatives of M and N with respect to their respective variables are both zero, the given differential equation satisfies the condition for exactness:
∂(M)/∂(y) = ∂(N)/∂(x)
Thus, we can conclude that the given differential equation is exact.
Explanation:
The given differential equation has the form M(x, y)dx + N(x, y)dy = 0, where M = P(x) and N = Q(y). For a differential equation to be exact, it must satisfy the condition ∂(M)/∂(y) = ∂(N)/∂(x).
In this case, since M = P(x) does not involve y and N = Q(y) does not involve x, the partial derivatives with respect to y and x, respectively, are zero. Therefore, ∂(M)/∂(y) = ∂(N)/∂(x) = 0.
Since the partial derivatives are equal to zero, the given differential equation satisfies the condition for exactness. Hence, option C, "Is always exact," is the correct answer.
Note: The fact that P(x) = x and Q(y) = y are not necessary conditions for the exactness of the differential equation. The equation is exact regardless of the specific forms of P(x) and Q(y).
If P(x) and Q(y) are arbitrary functions of x and y respectively, then...
Proof : The given differential equation is
P(x)dx+Q(y)dy = 0 ...(i)
Comparing it with
Mdx + Ndy = 0 ...(ii)
∴ M = P(x) and N = Q(y)
is always satisfied.
⇒ D.E. (i) is always exact.