f(x)=log1/3^(x^2+1)-log3^(x+3)的单调区间!

f(x)=log1/3^(x^2+1)-log3^(x+3)的单调区间!

f(x)=-log3^(x²+1)-log3^(x+3)
=-log3^[(x²+1)(x+3)]
f'(x)=-ln3(3x²+6x+1)/[(x²+1)(x+3)]
-3 < x < -1 - √6/3时
f'(x)