Answer:All real numbers except for 0 and 4.
Step-by-step explanation:
The denominator cant be zero so we take it and equal it to zero. For the denominator to equal to zero, either x = 0 or x=4 yields 0.
(t^2-1)(t^2-4)
so t=(-1, 1, -2, 2)
Time moves in one direction to our knowledge so disregard negative values.
depending on context, 1st and 2nd yr
