86707 ∫01|5x−3|dx is equal to
(C) : ∫01|5x−3|dx|5x−3|={5x−3x≥35−(5x−3)x≤35I=∫01|5x−3|dx=∫03/5−(5x−3)dx+∫3/51(5x−3)dx=−[52x2−3x]03/5+[5x22−3x]3/51=−[(52×(35)2−3×35)−(0−0)]+[(52×1−3×1)−(52×925−95)]=−[(52×(35)2−3×35)]+[(52−3)−(4550−95)]=−4550+95−12−4550+95=1310
86728 ∫01log(1x−1)dx is equal to
(B) : Given,∫01log(1x−1)dxLet, I=∫01log(1x−1)=∫01log(1−xx)dxI=∫01log(1−(1−x)1−x)dxI=∫01log(x1−x)dxAdding equation (i) and (ii)2I=∫01log(1−xx)dx+∫01log(x1−x)dx=∫01log(1−xx⋅x1−x)dx=∫01log1dx=0∴I=0
86699 ∫21|[x−1]|dx=(where, [.] is greater integer function)
(B) : ∫−21|[x−1]|dx=−2<x<1−2−1<x−1<1−1−3<x−1<0∴[x−1]=−3,−2,−1|[x−1]|=3,2,1∫−21|[x−1]|dx=∫−2+13dx+∫−102dx+∫011dx=3[x]−21+2[x]−10+[x]01=3(1)+2(1)+1=6
86700 ∫03[x]dx=where [x] is greatest integer function.
(A) : Given,∫010dx+∫121dx+∫232dx=[x]12+2[x]23=(2−1)+2(3−2)=1+2=3
86701 Evaluate ∫12x3−x+xdx
(C) : Let I=∫12x3−x+xdxThen, I=∫123−x3−(3−x)+3−xdxI=∫123−xx+3−xdxAdding equation (i) and (ii), we get-2I=∫121.dx=[x]12=2−1=1I=1/2