Answer:
dz / dt = -50
Step-by-step explanation:
To solve the chain rule must apply, we have all the necessary values to make the calculation, as follows:
using the chain rule, we find:
dz / dt = (∂z / ∂x) * (∂x / ∂t) + (∂z / ∂y) * (∂y / ∂t)
Evaluating when t = 9, we have to:
fx (6, 4) * g '(9) + fy (6, 4) * h '(9)
We know that g '(9) = −6; h '(9) = 4; fx (6, 4) = 9; fy (6, 4) = 1
Replacing:
(9 * -6) + (1 * 4) = -50
Por lo tanto dz / dt = -50
Answer:
jane will arrive at 3:41
Mira will arrive at 3:50
so the the difference in time is 9 minutes
—————-
The shaded area = Circle area - square area
circle area = 314
square area = 100
the the shaded area = 214
Answer:
£910
Step-by-step explanation:
let 3x and 7x be the initial amounts in their accounts, then after alterations
Terry has 3x + 220
Faye has 7x - 300
After these changes the amounts are equal, hence
7x - 300 = 3x + 220 ( subtract 3x from both sides )
4x - 300 = 220 ( add 300 to both sides )
4x = 520 ( divide both sides by 4 )
x = 130
Faye initially had 7 × £130 = £910 in her account
