The monotone decreasing interval of the function Log &; (3 + 2x-x ^ 2) is

The monotone decreasing interval of the function Log &; (3 + 2x-x ^ 2) is

Because the base number is 2, it's an increasing function
Let Log &; (3 + 2x-x ^ 2) be a decreasing function
Then we must make 3 + 2x-x ^ 2 a decreasing function
First, the domain of definition is solved
3+2x-x^2>0
x^2-2x-3