Question

If f(x) = |x – 25| and g(x) = f(f(x)) then for x > 50, g′(x) is equal to –

• A. 0
• B. 1
• C. 25
• D. None of these

Answer 1

Answer: (B)

1

Answer 2

g(x) = f(f(x)) = f(|x – 25|) = | |x – 25| – 25|

for x > 50, g(x) = |x – 25 – 25| = |x – 50|

= x – 50, g'(x) = 1