Let f"(x)=3x^3+2x-2 and f(x) have critical numbers -2,0, and 1. Determine if any of the critical numbers gives a relative minimun using the second derivative test.
the relative minimum ocuurs when the second derivative yields a positive value and it is at 1
thank you
Can you help me with one more please?
yes ofcourse
Let f be a twice-differentiable function whose derivative, f'(x), is decreasing for all x. Which of the folowing must be true for all x? I. f(x)<0 II.f'(x)<0 III.f"(x)<0
iii f''x<0
slope of the graph of the second derivative must be less than zero for it to decrease for all values of x
So is it only at f"(x)<0 or can it be f"(x)<0 and f'(x)<0
given only f'x is decresing for all values of x ,doesn't mean f(x) is decresing
okay thanks
Join our real-time social learning platform and learn together with your friends!