Given Integral Simplification: We are given the integral: ∫4x2−12x+10(16x−20)dx First, we should try to simplify the denominator if possible and see if we can factor it. The denominator is a quadratic expression, so we can attempt to factor it by completing the square or using the quadratic formula.
Completing the Square: The quadratic expression in the denominator is:4x2−12x+10To complete the square, we can factor out the 4 from the first two terms to get:4(x2−3x)+10Now, we need to add and subtract the square of half the coefficient of x inside the parentheses, which is (3/2)2=9/4.4(x2−3x+9/4−9/4)+104(x−3/2)2−4(9/4)+104(x−3/2)2−9+104(x−3/2)2+1Now we have the denominator in the form of a perfect square plus a constant.
Substitution for Simplification: Next, we can rewrite the integral with the simplified denominator: ∫4(x−23)2+1(16x−20)dxNow, we should look for a substitution that will simplify the integral. A good substitution would be to let u equal the expression inside the square, i.e., u=x−23.
Performing Substitution: Let's perform the substitution:u=x−23Then, du=dx, since the derivative of x with respect to x is 1 and the derivative of a constant is 0.Now we need to express the numerator 16x−20 in terms of u. To do this, we solve for x in terms of u:du=dx0
Splitting into Two Integrals: Substitute x in the numerator: 16x−20=16(u+23)−20=16u+24−20=16u+4 Now we can rewrite the integral in terms of u: ∫4u2+1(16u+4)du
First Integral Simplification: We can split the integral into two separate integrals: ∫4u2+116udu+∫4u2+14duNow, we can simplify each integral further. For the first integral, we can factor out constants and for the second integral, we can use a standard integral formula.
Second Integral Simplification: The first integral becomes: 4∫4u2+14uduWe can factor out the 4 from the numerator and cancel it with the 4 in the denominator:∫4u2+14udu=∫u2+(41)udu
Integrating Both Parts: The second integral is a standard form:∫4u2+14duWe can factor out the 4 from the denominator:∫4(u2+(1/4))4du= ∫u2+(1/4)duThis is the integral of the form ∫u2+a2du, which has a standard result of (1/a)arctan(u/a)+C.
Final Result Substitution: Now we integrate both parts:For the first integral, we have:∫u2+(41)udu=21ln∣u2+(41)∣+C1For the second integral, we have:∫u2+(41)du=2arctan(2u)+C2
Final Result Substitution: Now we integrate both parts:For the first integral, we have:∫u2+(41)udu=21ln∣u2+(41)∣+C1For the second integral, we have:∫u2+(41)du=2arctan(2u)+C2Combining both integrals, we get the final result:21ln∣u2+(41)∣+2arctan(2u)+CNow we need to substitute back for u to get the result in terms of x:u=x−23
Final Result Substitution: Now we integrate both parts:For the first integral, we have:∫u2+(1/4)udu=21ln∣u2+(1/4)∣+C1For the second integral, we have:∫u2+(1/4)du=2arctan(2u)+C2 Combining both integrals, we get the final result:21ln∣u2+(1/4)∣+2arctan(2u)+CNow we need to substitute back for u to get the result in terms of x:u=x−23 Substituting back, we get:21ln∣(x−23)2+(1/4)∣+2arctan(2(x−23))+CThis is the indefinite integral of the given function.
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