You can put this solution on YOUR website! Let's start with the . Once one has worked with exponents and logarithms enough, you learn that a power of 2 (or any other positive number number) can result in any positive number! What a power of 2 can't be is zero or negative. So the part can have a value of any positive number.
The minus in front of the turns all those positive numbers negative. So can result in any negative number. IOW, any number less than zero.
If you take all those numbers than zero and then add 2, you end up with all numbers less than 2. This is the range of your function: all numbers less than 2.
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