JEE Main2012MathematicsDifferential EquationsActual
Let y(x) be a solution of (2+ x (1+y) d y) d x = x . If y(0)=2 , then y ( 2 ) equals
Options
- A5 2
- B2
- C7 2
- D3
Correct answer
C. 7 2
Step-by-step solution
Given differential equation is (2+ x (1+y) d y d x = x which can be rewritten as d y 1+y = x 2+ x d x Integrate both the sides, we get aligned & d y 1+y = x d x 2+ x & (1+y)= (2+ x)+ C & 1+y=C(2+ x) & Given y(0)=2 & 1+2=C[2+ 0] C= 3 2 aligned Now, y ( 2 ) can be found as 1+y= 3 2 (2+ 2 ) 1+y= 9 2 y= 7 2 Hence, y ( 2 )= 7 2