Evaluate the following integrals –

Let


Let us assume




We know and derivative of a constant is 0.


2x – 5 = λ(0 + 3 – 2x2-1) + μ


2x – 5 = λ(3 – 2x) + μ


2x – 5 = –2λx + 3λ + μ


Comparing the coefficient of x on both sides, we get


–2λ = 2 λ = –1


Comparing the constant on both sides, we get


3λ + μ = –5


3(–1) + μ = –5


–3 + μ = –5


μ = –2


Hence, we have


Substituting this value in I, we can write the integral as






Let


Now, put 2 + 3x – x2 = t


(3 – 2x)dx = dt (Differentiating both sides)


Substituting this value in I1, we can write




Recall







Let


We can write







Hence, we can write I2 as



Recall





Substituting I1 and I2 in I, we get



Thus,


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