求导ln和y=e^xc和d 2题 求导 />

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求导ln和y=e^xc和d 2题 求导 />
求导ln和y=e^x
c和d 2题 求导 />

求导ln和y=e^xc和d 2题 求导 />
(c)
y =ln[(x^2+2)/(7-x^2-6x^3)]
y' = [(7-x^2-6x^3)/(x^2+2)]. [(x^2+2)/(7-x^2-6x^3)]'
= [1/(x^2+2)]. [(7-x^2-6x^3)(2x) -(x^2+2)(-2x-18x^2) ]/(7-x^2-6x^3)
= [1/(x^2+2)]. { 2x[ (7-x^2-6x^3) +(x^2+2)(1+9x) ] }/(7-x^2-6x^3)
=[1/(x^2+2)]. { 2x[ (7-x^2-6x^3) +(x^2+2)(1+9x) ] }/(7-x^2-6x^3)
= 6x(x^3+6x+3)/[(x^2+2)(7-x^2-6x^3)]
(d)
y=e^(3x^3).e^(-2x).e^2
=e^(3x^3-2x+2)
y' = e^(3x^3-2x+2) .(3x^3-2x+2)'
= (9x^2-2).e^(3x^3-2x+2)

这个看起来真的是很难的啊