Given: ∫(2x−3)32x−5e2xdx=(2x−3)2λe2x+C
Differentiating the right side:
dxd[(2x−3)2λe2x]
Let u=λe2x and v=(2x−3)2
Then u′=2λe2x and v′=4(2x−3)
Applying the quotient rule:
dxd[(2x−3)2λe2x]=(2x−3)4(2x−3)2⋅2λe2x−λe2x⋅4(2x−3)
=(2x−3)4λe2x[(2x−3)2⋅2−4(2x−3)]
=(2x−3)4λe2x(2x−3)[2(2x−3)−4]
=(2x−3)3λe2x[2(2x−3)−4]
Simplifying the numerator:
2(2x−3)−4=4x−6−4
=4x−10
=2(2x−5)
Therefore:
(2x−3)3λe2x⋅2(2x−5)=(2x−3)32λ(2x−5)e2x
The derivative must equal the original integrand:
(2x−3)32λ(2x−5)e2x=(2x−3)3(2x−5)e2x
Comparing coefficients:
2λ=1
λ=21