Answer
$-9/5 m/s$
Work Step by Step
First, we take the derivative of the original equation, $10 + 45/t+ 1$
when finding the derivative, we can eliminate the 10 since it has no exponent.
so we are left with $45/t+1$, which we can find the derivative using the quotient rule.
$(t+1) (0) - (1) (45) / (t+1)^2$
simplifies to $-45/ (t+1)^2$
the problem gives us t=4, which we can input for t.
$-45/ ( (4) +1)^2$
$-45/ 25 m/s$
$-9/5 m/s$
