Q3 of 20 Page 1

Let * be a binary operation on set of integers I, defined by a*b = 2a + b – 3. Find the value of 3*4.[CBSE 2011]

Given operation: a*b = 2a + b – 3


3*4 = 2 × 3 + 4 – 3


= 6 + 4 – 3


= 7


Hence, 3*4 = 7.


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