look up in or on the book?

[deumex]

what do you say? Look up in or on the book?
When do we say at? Look at page 12

[HCaulfield]

I would use look it up in your book. The idea behind this is that you have to open the book and look through it.

[MikeNewYork]

Originally Posted by deumex

what do you say? Look up in or on the book?
When do we say at? Look at page 12

We look something up in a book.

We open a book to page 12.
We look at page 12.
Something is written in a book, on page 12.