Question

Find minimum speed of a particle with trajectory

Answer 1

So here's what I told my professor and he confirmed it as right (though I am still unsure if it was really right):
1. Write the speed formula:
speed=9t4+4t−6−−−−−−−−√

2. Write the derivative of the speed and find where it's equal to 0:
ddt(9t4+4t−6−−−−−−−−√)

3. Write the second derivative of the speed and find where it's > 0:

Answer 2

the answer is o.........