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`int_(1)^(2)|x^(2)-3x+2|dx=?`A. `(-1)/(6)`B. `(1)/(6)`C. `(1)/(3)`D. `(2)/(3)`

Answer» `(x^(2)-3x+2)=(x-1)(x-2)`
`1 le x lt 2 implies (x^(2)-3x+2) le 0`
`implies |x^(2)-3x+2|=-(x^(2)-3x+2)`
`:. I=int_(1)^(2)-(x^(2)-3x+1)dx=int_(1)^(2)(-x^(2)+3x-2)dx`
`=[(-x^(3))/(3)+(3x^(2))/(2)-2x]_(1)^(2)=((-2)/(3)+(5)/(6))=(1)/(6)`.


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