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    				| 1. | Evaluate: `int(3x-2)/((x+1)^2(x+3)) dx` | 
| Answer» `Let ((3x-2))/((x+1)^(2)(x+3))=(A)/((x+1))+(B)/((x+1)^(2))+(C)/((x+3))` `implies (3x-2)-=A(x+1)(x+3)+B(x+3)+C(x+1)^(2).` Putting `x=-3` on both sides of (i) , we get `C=(-11)/(4).` Putting `x=-1` on both sides of (i), we get `B=(-5)/(2).` Comparing the coefficients of `x^(2)` on both sides of (i) ,we get `A+C=0impliesA=-C=(11)/(4).` `therefore ((3x-2))/((x+1)^(2)(x+3))=(11)/(4(x+1))-(5)/(2(x+1)^(2))-(11)/(4(x+3))` `implies int((3x-2))/((x+1)^(2)(x+3))dx=(11)/(4).int (dx)/((x+1))-(5)/(2).int (1)/((x+1)^(2))dx-(11)/(4).int(dx)/((x+3))` `=(11)/(4).log |x+1|+(5)/(2(x+1))-(11)/(4).log|x+3|+C` `=(11)/(4)/log|(x+1)/(x+3)|+(5)/(2(x+1))+C.` | |