GWD 10-34

sunjueliang

Q34:The function f is defined by f(x) = - 1/x for all nonzero

numbers x. If f(a) = - 1/2 and f(ab)

= 1/6, then b =
A. 3
B. 1/3
C. - 1/3
D. -3
E. –12

答案d, 应为a.

If f(a) = - 1/2 and f(ab)

= 1/6------f(b)=-1/3 ----b=3-----A,

请指正。谢谢！

recently

楼上错了，f(ab) = -1/ab = -1/a * 1/b = 1/6

-1/a= -1/2, b=-3