Complete the Square: First, complete the square for the quadratic in the denominator.2x2−4x+20=2(x2−2x+10)Now, to complete the square, we need to add and subtract (b/2)2 where b is the coefficient of x.So, (b/2)2=(2/2)2=1.Add and subtract 1 inside the parenthesis and factor out the 2.2(x2−2x+1+9)=2((x−1)2+9)
Rewrite the Integral: Now, rewrite the integral with the completed square.∫2x2−4x+201dx=∫2((x−1)2+9)1dxSimplify the integral by taking out the constant.=21×∫(x−1)2+91dx
Recognize Arctan Formula: Recognize the integral as a form of the inverse tangent function, arctan(u), where the integral of u2+a21du is a1⋅arctan(au)+C. Here, u=x−1 and a2=9, so a=3.
Apply Arctan Formula: Apply the arctan formula.(21)⋅∫(x−1)2+91dx=(21)⋅(31)⋅arctan(3x−1)+CSimplify the constants.=(61)⋅arctan(3x−1)+C
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