Intermediate Value Theorem to show that there is a root in a given equation/interval

Question: Use the Intermediate Value Theorem to show that there is a root of the given equation in the specified interval.

37.

x^4 + x - 3 = 0, (1,2)

What do I do for this question? Do I plug in 1 and 2 and try to estimate something in the middle, like I don't get what it is asking in the first place. Like what does "a root of the given equation in the specified interval" mean?

Any help would be greatly appreciated!

Thanks in advance!