Mathematics for IGCSE & O level - Vectors (Section 3 - No. 37)
If the vector [2, -1] represents a translation, which describes the move?
2 units left, 1 unit down
2 units right, 1 unit down
2 units left, 1 unit up
2 units right, 1 unit up
解释
Positive x is right, negative y is down.