Stepwise
Start practisingPractise

JAMB 2012 · UTME · Q21

The binary operation ∗* is defined on the set of integers such that p∗q=pq+p−qp * q = pq + p - q. Find 2∗(3∗4)2 * (3 * 4).

Worked solution (try it first)
  1. Work out the bracket first: 3∗4=12+3−4=113 * 4 = 12 + 3 - 4 = 11.
  2. Then 2∗11=2×11+2−11=22−92 * 11 = 2 \times 11 + 2 - 11 = 22 - 9.
  3. So 2∗(3∗4)=132 * (3 * 4) = 13, option B.

Report a problem with this question