How do you find the general solution of the differential equation dydx = y * e^(7x)?

The given differential equation is:

dy/dx = y * e7x

To solve this first-order linear differential equation, we can use the technique of separation of variables. The main idea is to rearrange the equation in a way that allows us to separate variables y and x.

1. **Rearranging the equation**: We can separate the variables:

dy/y = e7x dx

2. **Integrating both sides**: Now, we integrate both sides to isolate y:

∫ (1/y) dy = ∫ e7x dx

The left side integrates to:

ln|y| + C1

And the right side integrates to:

(1/7)e7x + C2

3. **Combining results**: Equating both integrals gives us:

ln|y| = (1/7)e7x + C

where $C = C2 – C1$ is a constant.

4. **Exponentiating to solve for y**: We can exponentiate both sides to solve for y:

|y| = e(1/7)e7x + C = e(1/7)e7x} * eC

This simplifies to:

|y| = A * e(1/7)e7x} where $A = e^C$ is a positive constant.

Thus, we can write:

y = ± A * e(1/7)e7x}

5. **Final form of the general solution**: Recognizing that ±A can be represented as a new constant K, we arrive at the final general solution:

y = K * e(1/7)e7x}

where K is any real constant. This is the general solution of the differential equation.

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