VECTORS 1

If u = 16i + 2j and v = 8i + 10j find 2u - 3v.

solution

= 2u - 3v

= 2(16i + 2j) - 3(8i + 10j)

= 32i + 4j - 24i - 30j

= (32i - 24i) + (4j - 30j)    [grouping like terms]

= 8i - 26j

Hence 2u + 3v = 8i - 26j .

TRY THIS..................

If u = 7i + 3j and v = 17i + 4j;  find 5u - 2v.