what is the position and acceleration at the instant when its velocity is zero?

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The position of an object is given by $${x(t)= 2.17+4.80t^2-0.100t^6}$$

Would I have to take the derivative of that in order to find velocity?

But from there how would I find the position and acceleration the instant velocity is zero? For time I thought about setting v to zero and solving to find the time but I don't know how that would really help me.

Would acceleration just be the derivative of v? Is there an exact way to find acceleration?

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The position of an object is given by

$${x(t)= 2.17+4.80t^2-0.100t^6}$$

Thus velocity of the object is given by x'(t) which is:

$$x'(t)=v(t) = 9.60t-0.600t^5$$

Since velocity is 0, we can solve for time:

$$0= 9.60t-0.600t^5$$

$$ t= -2,0,2$$

Since time can't be negative, and we probably want the positive t -value, let's use t = 2.

We then sub t = 2 into x(t) and a(t).

We can get a(t) by using the identity v'(t)=a(t)

$$v'(t)=a(t)=9.6-3t^4$$

Solving for t =2:

$$a(2)=9.6-3*2^4=-38.4$$

$${x(2)= 2.17+4.80*2^2-0.100*2^6=14.97}$$

Therefore, position and acceleration when velocity is equal to 0, is 14.97 $units$ and -39.4 $units/s^2$