已知f(X)=2lnx+(a-1)(x2-1)/x,求导求导过程

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已知f(X)=2lnx+(a-1)(x2-1)/x,求导
求导过程

你好!
f'(x)=2/x+(a-1)*[2x*x-(x^2-1)*1]/x^2
=2/x+(a-1)*[2x^2-x^2+1]/x^2
=2/x+(a-1)*(1+1/x^2)
=2/x+(a-1)/x^2 +a-1

解:
f(x)=2lnx+(a-1)(x^2-1)/x
f'(x)=2(lnx)'+(a-1)[(x^2-1)/x]'
=2/x+(a-1)[[(2x)x-(x^2-1)]/x^2]

f(x)=2lnx+(a-1)(x^2-1)/x
f'(x)=[2lnx+(a-1)(x^2-1)/x]'
=2(lnx)'+(a-1)[(x^2-1)/x]'
=2/x+(a-1)[(x^2-1)'x-(x^2-1)x']/x^2
=2/x+(a-1)(2x*x-x^2+1)/x^2
=2/x+(a-1)(x^2+1)/x^2

2㏑x的导数为2/x,(a-1)(x²-1)/x=(ax²-x² 1-a)/x的导数为(ax²-3x² 1-a)/x²=a-3 1/x²-a/x²,所以,f'(x)=2/x a-3 1/x²-a/x²