Separate variables: First, we need to solve the differential equation (dxdy=3y). This is a separable differential equation, so we can separate the variables y and x.
Integrate both sides: We move dy to one side and all the x terms to the other side to integrate. So we get (1/y)dy=3dx.
Find integration constant: Now we integrate both sides. The integral of (1/y)dy is ln∣y∣, and the integral of 3dx is 3x. So we have ln∣y∣=3x+C, where C is the integration constant.
Find particular solution: We need to find the value of C using the initial condition y(0)=3. Plugging in the values, we get ln∣3∣=3⋅0+C, which simplifies to ln(3)=C.
Exponentiate both sides: Now we have the particular solution ln∣y∣=3x+ln(3). To find y, we exponentiate both sides to get ∣y∣=e3x+ln(3).
Drop absolute value: Since y is positive from the initial condition y(0)=3, we can drop the absolute value to get y=e3x⋅eln(3).
Simplify exponential term: We simplify eln(3) to just 3, so the equation becomes y=3e3x.
Substitute x value: Now we need to find y(ln(2)). We substitute x with ln(2) to get y(ln(2))=3e3ln(2).
Simplify exponential term: We use the property of exponents to simplify e3ln(2) to (eln(2))3, which is 23.
Calculate final result: So y(ln(2))=3×23. Calculating 23 gives us 8, and multiplying by 3 gives us 24.
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