Thread: Partial Fractions

∫(4x²-11x+4)/(x³-3x²+2x) dx

i know the bottom part breaks up into
x(x²-3x+2) = x(x-2)(x-1)

where do i go form there?

Originally Posted by hlpplz

∫(4x²-11x+4)/(x³-3x²+2x) dx

i know the bottom part breaks up into
x(x²-3x+2) = x(x-2)(x-1)

where do i go form there?

multiplying both sides of the equation by the LCD, we have:



now can you finish?

Originally Posted by hlpplz

∫(4x²-11x+4)/(x³-3x²+2x) dx

i know the bottom part breaks up into
x(x²-3x+2) = x(x-2)(x-1)

where do i go form there?

∫(4x²-11x+4)/(x³-3x²+2x)



Find A B & C And then integrate

its too late

ok so i multiplied by the LCD and got

4x²-11x+4 = A(x-2)(x-1) + B(x)(x-1) + C(x)(x-2)
4x²-11x+4 = A(x²-3x+2) + B(x²-x) + C(x²-2x)

isolating x² = A + B + C = 4
isolating x = -3A - B - 2C = -11
isolating # = 2A = 4

solving for A,B,C i got

A= 2, B=-7, C=9

∫ A/x + B/(x-2) + C/(x-1) dx

∫ 2/x - 7/(x-2) + 9/(x-1) dx

2∫ 1/x - 7∫ 1/(x-2) + 9∫ 1/(x-1) dx

2ln⎮x⎮ - 7ln⎮x-2⎮ + 9ln⎮x-1⎮

Good?

Originally Posted by hlpplz

ok so i multiplied by the LCD and got

4x²-11x+4 = A(x-2)(x-1) + B(x)(x-1) + C(x)(x-2)
4x²-11x+4 = A(x²-3x+2) + B(x²-x) + C(x²-2x)

isolating x² = A + B + C = 4
isolating x = -3A - B - 2C = -11
isolating # = 2A = 4

solving for A,B,C i got

A= 2, B=-7, C=9

∫ A/x + B/(x-2) + C/(x-1) dx

∫ 2/x - 7/(x-2) + 9/(x-1) dx

2∫ 1/x - 7∫ 1/(x-2) + 9∫ 1/(x-1) dx

2ln⎮x⎮ - 7ln⎮x-2⎮ + 9ln⎮x-1⎮ +c

Good?

Yes

Thank you very much