## Calculus (3rd Edition)

Compare the given equations with the linear equation $a_{n}(x) y^{(n)}+a_{n-1}(x) y^{(n-1)}+\cdots+a_{1}(x) y^{\prime}+a_{0}(x) y=b(x)$ We see that: ( a) It is not linear and first order. Notice $y^5$ term. ( b) It is linear and first order. ( c) It is not linear and third order. Notice the $\sqrt y$ term. ( d) It is linear and second order.