How do i find the domain and range of these functions?

f(x)=x+1
f(x)=2/x
f(x)=(x+1)/(2x-5)
f(x)=sqrt(x+1)
f(x)=sqrt(3x-9)
f(x)=1/sqrt(x-5)

for domain, look at what values of x are allowed. For instance, in the last, x cannot be 5, you cannot have sqrt0 in the denominator.

For range of f(x), put extreme values in for x, see what the f(x) is.