ds test 5 # 23

[dunkin77]

Hi,

The answer is A) but I cant figure out why.... could anyone please explain? (I thought the answer was D) cause both a) and 2) look addition)


If ☉ denotes a mathematical operation, does
x☉y=y☉x for all x and y?
(1) For all x and y, x☉y = 2(x2 + y2).
(2) For all y, 0☉y = 2 y2

[Neo2000]

Question can be answered from statement 1 alone. Statement 1 defines the function in terms of both Xand Y and you can prove tht X0Y = YoX whereas statement2 ONLY defines in terms of Y. What is part played by X? is it X2 or X3 or....

[hillzheng]

I agree with neo2000