Final answer:
The cross product of vectors a and b is (-8, -8, 6). The cross product is not commutative, so b x a is not equal to (-8, -8, 6).
Step-by-step explanation:
To find the cross product of vectors a and b, we can use the formula (axb) = (aybz - azby)i - (axbz - azbx)j + (axby - aybx)k. Substituting the values from a = (2,-1,5) and b = (2,2,1), we get:
(2x1 - 5x2)i - (2x5 - 1x2)j + (2x2 - (-1)x2)k
= -8i - 8j + 6k
Therefore, the cross product a x b is (-8, -8, 6).
The cross product is not commutative, so a x b is not the same as b x a. Hence, b x a is not equal to (-8, -8, 6).