Chapter 4 - Vector Spaces - 4.8 Applications of Vector Spaces - 4.8 Exercises - Page 219: 3

(a) $x$ is not a solution. (b) $e^x$ is not a solution. (c) $e^{-x}$ is a solution. (d) $e^{-x}$ is not a solution.

Consider the linear differential equation $y^{\prime \prime \prime}+y^{\prime \prime}+y^{\prime}+y=0$ (a) $x$ is not a solution. (b) $e^x$ is not a solution. (c) $e^{-x}$ is a solution. (d) $e^{-x}$ is not a solution.