The DE dy/dx = y/x is best solved by:
- Variable separable (the easiest first try)
- Bernoulli's substitution v = y^(1−n)
- Integrating factor as linear DE
- Auxiliary equation as second-order
Show answer and solution
Correct answer: A. Variable separable (the easiest first try)
We have dy/dx = y/x → dy/y.
That is dy/dx = dx/x → ln|y|.
That is dy/dx = ln|x| + C → y.
So dy/dx = Ax.
**Variable separable:** separate variables, integrate both sides.