we are given

where 0<b<1
Domain:
domain is all possible values of x for which any function is defined
so, we can select any values of x for which function
it will be defined for all real x
so, domain is

Range:
Range is all possible values of y for which x is defined
we are given that b is positive
so, value of function will always be positive
so, range is

or
y>0
x-intercept:
we can set f(x)=0
and then we can solve for x

x is undefined
so, x-intercept does not exist
Increasing or decreasing:
Since, 0<b<1
so, b is positive value less than 1
so, as we increase value of , b^x will keep decreasing
so, this is decreasing