Question

What are congruent functions (in this context)?:
http://www.tiikoni.com/tis/view/?id=1d7c330

(I know the answer to that problem is A, but that's not what this question is about - I want to know what exactly congruence means in this context, because I can't find anything that is both simple to understand and relevant to this context.)

Any input would be very much appreciated!

Answer 1

seems to be that if one graph can be shifted and flipped and rotated to fit on another graph, then they are the same, or equal, or congruent graphs

think congruent triangles, or other shapes. placement doesnt affect equality

Answer 2

sin(x) is congruent to cos(x) simply because it is a horizontal shift of cos(x) is a good eample

Answer 3

Thanks @amistre64!