Which statement best describes how to determine whether f(x) = x2 – x + 8 is an even function?
a. Determine whether –x2 – (–x) + 8 is equivalent to x2 – x + 8.
b. Determine whether (–x)2 – (–x) + 8 is equivalent to x2 – x + 8.
c. Determine whether –x2 – (–x) + 8 is equivalent to –(x2 – x + 8).
d. Determine whether (–x)2 – (–x) + 8 is equivalent to –(x2 – x + 8).