- #1

dagg3r

- 67

- 0

**Differntiation! Bloody Confusing!**

HI guys help me out here with some differentitaion problems i'll post here what i have done and show me the way to go thanks

1. find dx/dt where x=(4-t)^5t

i tried using the chain rule but it doesn't work though cos you got that t constant do i use the logarithic way of differntiation so log X=5t*log(4-t) then i diff this?

2. A red car is traveling east towards an intersection at a speed of 80km/hr while a blue car simultaneously traveling north away from the intersection at a speed of 60 km/hr. If the red car is 4km from the intersection and the blue car is 3km from the intersection what is the rate of change the cars are changing?

i drew pictures of this then started to think to try and use pythagoras and possibly use some differentiation there applying the direction changes of negatives and positive but got lost and somebody point me the steps on to solve this problem thanks