求定积分,

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求定积分,求定积分,求定积分,令√5-4x=t5-4x=t²x=(5-t²)/4dx=-t/2dt原式=∫(3,1)(5-t²)/(4t)·(-t/2)dt=1/8∫(1

求定积分,
求定积分,

求定积分,
令√5-4x=t
5-4x=t²
x=(5-t²)/4
dx=-t/2dt
原式=∫(3,1)(5-t²)/(4t)·(-t/2)dt
=1/8∫(1,3)(5-t²)dt
=1/8×(5t-t³/3)|(1,3)
=1/8×[15-9-(5-1/3)]
=1/8×(4/3)
=1/6