NTA Abhyas JEE Main2020MathematicsDifferential EquationsPractice
The solution of the differential equation x c o s y d y d x + sin y = 1 is (Here, x > 0 and λ is an arbitrary constant)
Options
- Ax - x c o s x = λ
- Bx + x c o s x = λ
- Cx - x s i n y = λ
- Dx + x c o s y = λ
Correct answer
C. x - x s i n y = λ
Step-by-step solution
Let, sin y = t ⇒ cos y d y d x = d t d x ∴ the equation becomes x d t d x + t = 1 or x d t d x = 1 - t ⇒ d t 1 - t = d x x On integrating, we get, - ln 1 - t = ln x + ln C or 1 1 - t = C x i.e. 1 - sin y x = 1 C = λ s a y