Differentiate the function.
$ f(t) = 1.4t^5 - 2.5t^2 + 6.7 $
he has closed when you read here. So we have our do you over deep team of 1.45 t fifth power minus 2.5 T square plus 6.7. Well, then this is equal to 17 to the fourth power, Linus by T first power. And then we have a constant, so it's equal to zero. So our answer a 70 to the fourth Power minus five t.