h(x)=[f(x)-a(x+1)ln(x+1)]+aln(x+1)-2a(x-1) f(x)=3ax^3+2bx^2-a^x
问题描述:
h(x)=[f(x)-a(x+1)ln(x+1)]+aln(x+1)-2a(x-1) f(x)=3ax^3+2bx^2-a^x
答
h'(x) = f'(x) - a(x+1)*1/(x+1) - aln(x+1) + a/(x+1) - 2a
= 9ax^2 + 4bx - a^x*lna - a - aln(x+1) + a/(x+1) - 2a
= 9ax^2 + 4bx - a^x*lna - 3a - aln(x+1) + a/(x+1)
主要就是复合函数求导.