Q9 of 123 Page 3

The binary operation * defined on R×R → R is defined as a*b = 2a + b. Find (2*3)*4.

Given that * is an operation that is valid for the following Domain and Range R×R→R and is defined by a*b = 2ab.


We need to find the value of (2*3)*4


According to the problem the binary operation involving * is true for all real values of a and b.


⇒ (2*3)*4 = ((2×2) + 3)*4


⇒ (2*3)*4 = (4 + 3)*4


⇒ (2*3)*4 = 7*4


⇒ (2*3)*4 = (2×7) + 4


⇒ (2*3)*4 = 14 + 4


⇒ (2*3)*4 = 18


∴ The value of (2*3)*4 is 18.


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