VECTORS 1

If u = 6i + 2j and v = 7i + 10j find 2u - 3v

solution

= 2u - 3v

= 2(6i + 2j) - 3(7i + 10j)

= 12i + 4j - 21i - 30j

= (12i + 21i) + (4j - 30j)

= 33i - 26j

Hence 2u - 3v = 33i - 26j

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

If u = 9i + 3j and v = 2i + 4j;  find 2u + 3v.