Question
Mathematics Question on Differential equations
The solution of the differential equation xdy + ydx = 0 is:
A
xy = c
B
x2+y2=c
C
xy log x = 1
D
log xy = c
Answer
xy = c
Explanation
Solution
Given, xdy + ydx = 0 Divide both sides above equation by xy, We get, dydx+ydy=0 Integrating it on both sides, we get log x + log y = log c ⇒ log xy = log c ⇒ xy = c.