Question

What is the range of the function y=2x^{2} +4x-5 ?

Answer 1

logarithmic functions: f(x)=log(x)
logarithmic functions are not defined for non positive argument so check where the argument is ≤0.

log(x−2) ⇒ x−2=0 , x=2 
x−2≤0 , x≤2
f(x) is defined for x≤2, so the domain is (2,∞)
The range is R.