Answer:
10 kph
Step-by-step explanation:
Find the speed of the current of the river.
20/(20 - c) + 180/(20 + c) = 8
20(20 + c) + 180(20 - c) = 8(400 - c^2)
8c^2 - 160c + 800 = 0
8(c^2 - 20c + 100) = 0
8(c - 10)^2 = 0
c = 10
The speed of the current of the river is 10 km/hour.
If you're just starting calculus, perhaps you're asking about using the definition of the derivative to differentiate
.
We have

Expand the numerator using the binomial theorem, then simplify and compute the limit.

In general, the derivative of a power function
is
. (This is the aptly-named "power rule" for differentiation.)
The answer is lizeth earns 0.35 cents more per hour. beacuse 66 divided by 8 =8.25 then 68.80 divided by 8 is 8.60 then if you subtract 8.60-8.25 it equals 0.35
Answer:
75%
Step-by-step explanation:
Happy Friday!