You have to do speed over time to find out the distance the tourist will have to cover. (Speed multiplied by time= distance)
<span>Differentiating :
y' = 1 + sec^2(x),
</span><span>
cosπ=−1</span><span>
plug in pi = -1 ,for x:
1 + sec^2(pi) = 1 + (-1)^2
= 2</span>
