The Differential Equation $x y d x + \left( x ^ { 2 } + y ^ { 2 } \right) d y = 0$

question 1

Multiple Choice

The differential equation $x y d x + \left( x ^ { 2 } + y ^ { 2 } \right) d y = 0$ is

• A) exact with solution \(x ^ { 2 } y / 2 + y ^ { 3 } / 3 = c\)
• B) exact with solution \(x ^ { 2 } y / 2 + y ^ { 2 } / 2 = c\)
• C) exact with solution \(x ^ { 2 } y / 2 + y ^ { 3 } / 3 + c\)
• D) not exact but having an integrating factor x
• E) not exact but having an integrating factor y

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