If y=3e2x+2e3xy=3 e^{2 x}+2 e^{3 x}, prove that d2ydx2−5dydx+6y=0\frac{d^{2} y}{d x^{2}}-5 \frac{d y}{d x}+6 y=0.

Answer: The given equation d2ydx2−5dydx+6y=0\frac{d^{2} y}{d x^{2}}-5 \frac{d y}{d x}+6 y=0 is proven to be true.

Step-by-step solution

Step 1: Find the first derivative

To prove the given equation, we first need to find the first and second derivatives of yy with respect to xx. We start by differentiating the given function y=3e2x+2e3xy = 3e^{2x} + 2e^{3x} once.

Step 2: Calculate the first derivative

Using the chain rule, the derivative of eaxe^{ax} is aeaxae^{ax}. Applying this, the derivative of 3e2x3e^{2x} is 3⋅2e2x=6e2x3 \cdot 2e^{2x} = 6e^{2x}, and the derivative of 2e3x2e^{3x} is 2⋅3e3x=6e3x2 \cdot 3e^{3x} = 6e^{3x}.

Step 3: Find the second derivative

Now we differentiate the first derivative, 6e2x+6e3x6e^{2x} + 6e^{3x}, to find the second derivative of yy with respect to xx.

Step 4: Calculate the second derivative

Again, applying the chain rule, the derivative of 6e2x6e^{2x} is 6⋅2e2x=12e2x6 \cdot 2e^{2x} = 12e^{2x}, and the derivative of 6e3x6e^{3x} is 6⋅3e3x=18e3x6 \cdot 3e^{3x} = 18e^{3x}.

Step 5: Substitute into the equation

Now we substitute the expressions for yy, dydx\frac{dy}{dx}, and d2ydx2\frac{d^2y}{dx^2} into the given equation d2ydx2−5dydx+6y=0\frac{d^{2} y}{d x^{2}}-5 \frac{d y}{d x}+6 y=0.

Step 6: Simplify the expression

Distribute the coefficients and expand the terms. We will then group like terms (e2xe^{2x} terms and e3xe^{3x} terms) to simplify the expression.

Step 7: Combine like terms

Combine the coefficients for e2xe^{2x} and e3xe^{3x} terms. We find that (12−30+18)=0(12 - 30 + 18) = 0 and (18−30+12)=0(18 - 30 + 12) = 0, which proves the equation is equal to zero.

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