Common Core Standards: Math
5. Multiply a vector by a scalar.
Students shouldn't be scared of the word "scalar." A scalar is just a number without direction, like the number on your scale (and no, we aren't calling you fat).
- Represent scalar multiplication graphically by scaling vectors and possibly reversing their direction; perform scalar multiplication component-wise, e.g., as c(vx, vy) = (cvx, cvy).
- Compute the magnitude of a scalar multiple cv using ||cv|| = |c|v. Compute the direction of cv knowing that when |c|v ≠ 0, the direction of cv is either along v (for c > 0) or against v (for c < 0).