Final answer:
The differential equation provided by the student seems to contain a typo and is not in proper format for solving. Clarification on the correct form of the equation is required before proceeding to solve using techniques like separation of variables or integration by parts.
Step-by-step explanation:
The student has provided the differential equation d'' - e^-d = 0, which appears to be incorrect due to a typo. The correct form of a second-order differential equation typically involves a dependent variable, often denoted by y, x, or d, and its derivatives. For instance, the expression could be something like dd''/dx^2 - e^-d = 0 if d is the dependent variable and x is the independent variable.
However, given the information provided isn't sufficient to solve this equation, I would advise the student to double-check the equation and ensure proper formatting and notation. Once clarified, techniques such as separation of variables, integration by parts, or substitution might be applicable to solve the corrected differential equation.