Question

Let * be a binary operation defined by a * b = 3a + 4b − 2. Find 4 * 5.

Answer 1

Given: a * b = 3a + 4b − 2

Here, 

 4 * 5 = 3 (4) + 4 (5)\[-\] 2 

= 12 + 20 \[-\] 2 

= 30