定积分∫(上限1,下限-1)x/√(5-4x)dx

问题描述:

定积分∫(上限1,下限-1)x/√(5-4x)dx

∫x/√(5-4x)dx (-1→1)
=-(1/4)∫(5-4x-5)/√(5-4x)dx (-1→1)
=-(1/4)∫[√(5-4x) - 5/√(5-4x)]dx (-1→1)
=(1/16)∫[√(5-4x) - 5/√(5-4x)]d(5-4x) (-1→1)
=(1/16)[(2/3)(5-4x)^(3/2) - 10√(5-4x)] (-1→1)
=(1/16)[(2/3)(1-27) - 10(1-3)]
=1/6
过程、答案绝对错不了.