In: Advanced Math
Suppose f is a function defined for all real numbers which has a maximum value of 5 and a minimum value of −7. Label each of the following as MUST, MIGHT, or NEVER true. Explain, and if you say might, give an example of yes and an example of no.
A The maximum value of f(|x|) is 7.
B The maximum value of f(|x|) is 5.
C The maximum value of f(|x|) is 0.
D The minimum value of f(|x|) is 7.
E The minimum value of f(|x|) is 5.
F The minimum value of f(|x|) is 0.
G The maximum value of |f(x)| is 7.
H The maximum value of |f(x)| is 5.
I The maximum value of |f(x)| is 0.
J The minimum value of |f(x)| is 7.
K The minimum value of |f(x)| is 5.
L The minimum value of |f(x)| is 0.
Now suppose f is a continuous function defined for all real numbers which has a maximum value of 5 and a minimum value of −7. Which of the answers above stay the same (why?), and which change (to what, and why?)
(A) NEVER
(B) MIGHT
(C) MIGHT
(D) NEVER
(E) MIGHT
(F) MIGHT
(G) ALWAYS
(H) NEVER
(I) NEVER
(J) NEVER
(K) MIGHT
(L) MIGHT
All of the above answers remain the same as each of the above examples can be redefined using intervals so that f(x) becomes continuous.
For example, the last function in (L) can be redefined as
The properties will remain the same.