Question 21

-1

To find the value of f(1,2) - f(2,1), we first compute f(1,2) = (3*1)/(2*2) = 3/4 and f(2,1) = (3*2)/(2*1) = 3. Therefore, f(1,2) - f(2,1) = 3/4 - 3 = -1.

A) -1

This option is correct as it accurately reflects the calculation of f(1,2) - f(2,1). The detailed computation shows that after evaluating both functions, the difference indeed equals -1.

B) -0.5

This option is incorrect because it suggests a different result from the subtraction of the two function values. The correct calculation shows that the result is -1, not -0.5.

C) [Blank]

This option is not applicable as there is no content provided for this choice.

D) 0.5

This option is incorrect as it does not align with the calculated results. The difference of the two function evaluations does not yield 0.5, thus making this option invalid.

E) 1

This option is incorrect because it does not match the calculated difference. The correct evaluation leads to -1, ruling out 1 as a possible answer.

F) 2

This option is incorrect since it significantly deviates from the calculated difference of -1. Thus, it cannot be the correct answer.

Conclusion

The answer -1 is definitively correct as it is derived directly from the calculations of the binary function f for the provided values. All other options fail to represent the accurate result of the subtraction, highlighting the importance of precise mathematical evaluation in determining function values.