Question 8:
(2 marks)
The function \( f(x)=x^{3}+9 x^{2}-48 x-8 \) has relative minimum value at
a) \( (-8,-440) \)
b) \( (2,-60) \)
c) \( (2,60) \)
d) \( (-2,-60) \)
\( (2, -60) \)
Step 1 :\( f'(x) = 3x^2 + 18x - 48 \)
Step 2 :\( f''(x) = 6x + 18 \)
Step 3 :\( x = 2 \)
Step 4 :\( f(2) = -60 \)
Step 5 :\( (2, -60) \)