定积分∫[3,-1]|x-1|=?要有过程速度是定积分∫[3,-1]|x-1|dx=?少了个dx

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定积分∫[3,-1]|x-1|=?要有过程速度是定积分∫[3,-1]|x-1|dx=?少了个dx

定积分∫[3,-1]|x-1|=?要有过程速度是定积分∫[3,-1]|x-1|dx=?少了个dx
定积分∫[3,-1]|x-1|=?
要有过程速度
是定积分∫[3,-1]|x-1|dx=?少了个dx

定积分∫[3,-1]|x-1|=?要有过程速度是定积分∫[3,-1]|x-1|dx=?少了个dx
答:
从3到-1积分:-1

∫[3,-1]|x-1|dx
=∫[3,1] (x-1)dx + ∫[1,-1] (1-x) dx
显然
∫[3,1] (x-1)dx
=0.5x²-x 代入上下限3和1
=0.5*9 -3 -(0.5-1)
=2
而∫[1,-1] (1-x) dx
= x-0.5x² 代入上下限1和-1
=1 -0.5...

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∫[3,-1]|x-1|dx
=∫[3,1] (x-1)dx + ∫[1,-1] (1-x) dx
显然
∫[3,1] (x-1)dx
=0.5x²-x 代入上下限3和1
=0.5*9 -3 -(0.5-1)
=2
而∫[1,-1] (1-x) dx
= x-0.5x² 代入上下限1和-1
=1 -0.5 -(-1-0.5)
=2
所以
∫[3,-1]|x-1|dx
=∫[3,1] (x-1)dx + ∫[1,-1] (1-x) dx
=2+2
=4

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