✔ 最佳答案
題目1:∫(-1 to 5)_[x+1/2]dx
Sol
∫(-1 to 5)_[x+1/2]dx
=∫(-1 to -1/2-)_[x+1/2]dx+∫(-1/2+ to 1/2-)_[x+1/2]dx+∫(1/2+ to3/2-)_[x+1/2]dx
+∫(3/2+ to 5/2-)_[x+1/2]dx+∫(5/2+ to 7/2-)_[x+1/2]dx+∫(7/2+ to 9/2-)_[x+1/2]dx
+∫(9/2+ to 5)_[x+1/2]dx
=∫(-1 to -1/2-)_-1dx+∫(-1/2+ to 1/2-)_0dx+∫(1/2+ to 3/2-)_dx
+∫(3/2+ to 5/2-)_2dx+∫(5/2+ to 7/2-)_3dx+∫(7/2+ to 9/2-)_4dx+∫(9/2+ to 5)_5dx
=-1*(1/2)+1*1+2*1+3*1+4*1+5*(1/2)
=15
題目2:∫(-1 to 4)[x/2]dx
Sol
∫(-1 to 4)_[x/2]dx
=∫(-1 to 0-)_[x/2]dx+∫(0+to 2-)_[x/2]dx+∫(2+ to 4-)_[x/2]dx
=∫(-1 to 0-)_-1dx+∫(0+to 2-)_dx+∫(2+ to 4-)_2dx
=-1*1+1*2+2*2
=5