Let's think about this with our logic.
As #x# gets really, really, large, only the variable raised to the highest power will be significant. (For example, a billion squared is a billion times larger than just a billion.)
Therefore, #1-2x^2-3x# will be almost the same as #-2x^2# as #x# gets really, really, large.
Now, when #x# is really, really, large in#-2x^2#, then the answer will be an infinitely small number.
Therefore, as #x# gets really, really large, we will get closer and closer to #-oo#
Similarly, as #x# gets really, really, small, only the variable raised to the highest power will be significant. (For example, a billionth squared is a billion times smaller than just a billionth.)
Therefore, #1-2x^2-3x# will be almost the same as #-2x^2# as #x# gets really, really, small.
Now, when #x# is really, really, small in#-2x^2#, then the answer will be an infinitely small number.
Therefore, as #x# gets really, really small, we will get closer and closer to #-oo#