To multiply a vector by a scalar, multiply each term of the vector by the scalar.
Example: Given that a=2i+3j and b=i+j. Find:
- A=2i+3j
3a = 3(2i+3j) = 6i+9j
3a = 6i+9j
- 3a-2b
3a-2b = 3(2i+3j) + 2(i+j)
3(2i+3j) + 2(i+j) = (6i+9j) + (2i+2j)
(6i+9j) + (2i+2j) = 4i+7j
- B = i+j
2b = 2(i+j) = 2i+2j
2b = 2i+2j
- 4a+2b
4a+2b = 4(2i+3j) + 2(i+j)
4(2i+3j) + 2(i+j) = (8i+12j) + (2i+2j)
(8i+12j) + (2i+2j) = 10i+14j
4a+2b=10i+14j
