I'm confused on the following questions. (1) Find a vector that is perpendicular to (v_1,v_2). (2) Find two vectors that are perpendicular to (v_1,v_2,v_3. This homework set was written by the professor (it is review) before we actually get into the new material. The notation the book uses is that italics variables names are vectors. However in this homework set the professor uses bold face to denote vectors. I'm just unsure what the question is asking. Is (v_1,v_2) supposed to be 2 vectors in cartesian coordinates of the third dimension. Or does (v_1,v_2) denote one vector with components v_1 and v_2. I thought this review was going to be very straightforward, so I waited to the last minute (so I don't have time to ask him). Anyways, any clarification would be helpful. What do you think it would be? I know that: [tex] \vec v \cdot \vec y = 0 [/tex] means that the vectors are orthogonal to each other. and that [tex] \vec v \times \vec y = \vec a [/tex] means that [itex]\vec a[/itex] is orthogonal to both [itex]\vec v [/itex] and [itex] \vec y [/itex]. is that enough knowledge to complete the exercise? thanks in advance.