Question

Differential equation whose solution is $y = c x + c - c ^ { 3 }$, is

• A. $\frac { d y } { d x } = c$
• B. $y = x \frac { d y } { d x } + \frac { d y } { d x } - \left( \frac { d y } { d x } \right) ^ { 3 }$
• C. $\frac { d y } { d x } = c - 3 c ^ { 2 }$
• D. None of these

Answer 1

Answer: (B)

$y = x \frac { d y } { d x } + \frac { d y } { d x } - \left( \frac { d y } { d x } \right) ^ { 3 }$

Answer 2

Differentiating, we have $\frac { d y } { d x } = c$

Hence differential equation is, $y = x \frac { d y } { d x } + \frac { d y } { d x } - \left( \frac { d y } { d x } \right) ^ { 3 }$ .