Skip to main contentSkip to solution

If ∫2x−5(2x−3)3e2xdx=λe2x(2x−3)2+C\int \frac{2x - 5}{(2x - 3)^3} e^{2x} dx = \frac{\lambda e^{2x}}{(2x - 3)^2} + C, where CC is an arbitrary constant then the value of λ\lambda is

Solution

✅ Correct Option: 1

Given: ∫2x−5(2x−3)3e2xdx=λe2x(2x−3)2+C\int \frac{2x - 5}{(2x - 3)^3} e^{2x} dx = \frac{\lambda e^{2x}}{(2x - 3)^2} + C

Differentiating the right side:

ddx[λe2x(2x−3)2]\frac{d}{dx}\left[\frac{\lambda e^{2x}}{(2x - 3)^2}\right]

Let u=λe2xu = \lambda e^{2x} and v=(2x−3)2v = (2x-3)^2

Then u′=2λe2xu' = 2\lambda e^{2x} and v′=4(2x−3)v' = 4(2x-3)


Applying the quotient rule:

ddx[λe2x(2x−3)2]=(2x−3)2⋅2λe2x−λe2x⋅4(2x−3)(2x−3)4\frac{d}{dx}\left[\frac{\lambda e^{2x}}{(2x - 3)^2}\right] = \frac{(2x-3)^2 \cdot 2\lambda e^{2x} - \lambda e^{2x} \cdot 4(2x-3)}{(2x-3)^4}

=λe2x[(2x−3)2⋅2−4(2x−3)](2x−3)4= \frac{\lambda e^{2x}[(2x-3)^2 \cdot 2 - 4(2x-3)]}{(2x-3)^4}

=λe2x(2x−3)[2(2x−3)−4](2x−3)4= \frac{\lambda e^{2x}(2x-3)[2(2x-3) - 4]}{(2x-3)^4}

=λe2x[2(2x−3)−4](2x−3)3= \frac{\lambda e^{2x}[2(2x-3) - 4]}{(2x-3)^3}


Simplifying the numerator:

2(2x−3)−4=4x−6−42(2x-3) - 4 = 4x - 6 - 4

=4x−10= 4x - 10

=2(2x−5)= 2(2x - 5)

Therefore:

λe2x⋅2(2x−5)(2x−3)3=2λ(2x−5)e2x(2x−3)3\frac{\lambda e^{2x} \cdot 2(2x - 5)}{(2x-3)^3} = \frac{2\lambda(2x - 5)e^{2x}}{(2x-3)^3}


The derivative must equal the original integrand:

2λ(2x−5)e2x(2x−3)3=(2x−5)e2x(2x−3)3\frac{2\lambda(2x - 5)e^{2x}}{(2x-3)^3} = \frac{(2x - 5)e^{2x}}{(2x-3)^3}

Comparing coefficients:

2λ=12\lambda = 1

λ=12\lambda = \frac{1}{2}

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question