CBSE Class 12 Math 2012 Solved Paper
© examsiri.com
Question : 22 of 29
Marks:
+1,
-0
Find the particular solution of the following differential equation:
(x + 1) = - 1 ; y = 0 when x = 0
(x + 1) = - 1 ; y = 0 when x = 0
Solution:
(x + 1) = - 1
⇒ =
⇒ =
Integrating both sides, we get:
∫ = log |x + 1| + log C ... (1)
Let 2 - = t
∴ {dt}/{dy}$$
⇒ - =
⇒ dy = - dt
Substituting this value in equation 1 , we get:
∫ - = log |x + 1| + log C
⇒ - log |t| = log |C (x + 1)|
⇒ - log |2 - | = log |C (x + 1)|
⇒ = C (x + 1)
⇒ 2 - = ... (2)
Now, at x = 0 and y = 0, equation 2 becomes:
⇒ 2 - 1 =
⇒ C = 1
Substituting C = 1 in equation 2 , we get:
2 - =
⇒ = 2 -
⇒ =
⇒ =
⇒ y = log , (x ≠- 1)
This is the required particular solution of the given differential equation.
⇒ =
⇒ =
Integrating both sides, we get:
∫ = log |x + 1| + log C ... (1)
Let 2 - = t
∴ {dt}/{dy}$$
⇒ - =
⇒ dy = - dt
Substituting this value in equation 1 , we get:
∫ - = log |x + 1| + log C
⇒ - log |t| = log |C (x + 1)|
⇒ - log |2 - | = log |C (x + 1)|
⇒ = C (x + 1)
⇒ 2 - = ... (2)
Now, at x = 0 and y = 0, equation 2 becomes:
⇒ 2 - 1 =
⇒ C = 1
Substituting C = 1 in equation 2 , we get:
2 - =
⇒ = 2 -
⇒ =
⇒ =
⇒ y = log , (x ≠- 1)
This is the required particular solution of the given differential equation.
© examsiri.com
Go to Question: