∫(9 ,4)√x(1+√x)dx
=(2/3)∫(9,4) (1+x^1/2)d(x^3/2)
=2/3*((1+√x)x^3/2)|(9,4)-(1/2)∫(9,4)(x^3/2) (x^-1/2) dx
=2/3*((1+√x)x^3/2)|(9,4)-(1/4)(x^2)|(9,4)
如果积分限从4到9那么4*27-3*28-65/4=31/4
如果积分限从9到4那么3*28-4*27-65/4=-161/4
∫(9 ,4)√x(1+√x)dx
=(2/3)∫(9,4) (1+x^1/2)d(x^3/2)
=2/3*((1+√x)x^3/2)|(9,4)-(1/2)∫(9,4)(x^3/2) (x^-1/2) dx
=2/3*((1+√x)x^3/2)|(9,4)-(1/4)(x^2)|(9,4)
如果积分限从4到9那么4*27-3*28-65/4=31/4
如果积分限从9到4那么3*28-4*27-65/4=-161/4