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Part BCSIR NET December 2024the-second-solution-carries-a-power-not-a-constant

The second solution carries a power not a constant

Given that y1(x)=e(2x)y_{1}(x) = e^(2x) is a solution of the ordinary differential equation (ODE)xd2y/) x d^{2}y/dx2−(3+4x)^{2} - (3 + 4x)dy/dx + (4x + 6)y = 0, x > 0. Let y2=y2(x)y_{2} = y_{2}(x) be the solution of the ODE satisfying the conditions y2(1)=e2/4y_{2}(1) = e^{2}/4 and (dy2/_{2}/dx)(1)=3e2/2)(1) = 3e^{2}/2. Then which of the following statements is true?

  1. A.y2y_{2} is a strictly increasing function on (0,∞)(0, \infty)✓ Correct
  2. B.e(−2x)y2(x)→1e^(-2x)y_{2}(x) \to 1 as x→∞x \to \infty
  3. C.y2y_{2} is a strictly decreasing function on (0,∞)(0, \infty)
  4. D.e(−2x)y2(x)→0e^(-2x)y_{2}(x) \to 0 as x→∞x \to \infty

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward, and why this one tests execution slip.

See pricing

50 are analysed free — try those first.

The trap it tests

Execution slip

The idea was right. The computation was not.

Drill statements like this

Related counterexample: W(f, g) ≡ 0 implies f and g are linearly dependent

More on this topic

The chapter behind this: Linear ODE, Wronskian and systems — free to read

From Ordinary Differential Equations › Linear ODE, Wronskian, variation of parameters, systems

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