Answer:
a. 
b. 
Step-by-step explanation:
First, we need tot find a general expression for the amount of caffeine remaining in the body after certain time. As the problem states that every hour x percent of caffeine leaves the body, we must substract that percentage from the initial quantity of caffeine, by each hour passing. That expression would be:

Then, to find the amount of caffeine metabolized per hour, we need to differentiate the previous equation. Following the differentiation rules we get:

The rate is negative as it represents the amount of caffeine leaving the body at certain time.
I hope this helps you
-15+6= -9
-9+6= -3
-3+6=3
add 6
Answer with explanation:
For, a Matrix A , having eigenvector 'v' has eigenvalue =2
The order of matrix is not given.
It has one eigenvalue it means it is of order , 1×1.
→A=[a]
Determinant [a-k I]=0, where k is eigenvalue of the given matrix.
It is given that,
k=2
For, k=2, the matrix [a-2 I] will become singular,that is
→ Determinant |a-2 I|=0
→I=[1]
→a=2
Let , v be the corresponding eigenvector of the given eigenvalue.
→[a-I] v=0
→[2-1] v=[0]
→[v]=[0]
→v=0
Now, corresponding eigenvector(v), when eigenvalue is 2 =0
We have to find solution of the system
→Ax=v
→[2] x=0
→[2 x] =[0]
→x=0, is one solution of the system.
Answer:
Before coming back up to the surface the maximum depth, Cassidy went was 6.25 ft. below the water surface
Step-by-step explanation:
The height of Cassidy's diving platform above the water = 6 ft.
The equation that models her dive is d = x² - 7·x + 6
Where;
d = Her vertical position or distance from the water surface
x = Here horizontal distance from the platform
At Cassidy's maximum depth, we have;
dd/dx = d(x² - 7·x + 6)/dx = 2·x - 7 = 0
x = 7/2 = 3.5
∴ At Cassidy's maximum depth, x = 3.5 ft.
The maximum depth,
= d(3.5) = 3.5² - 7 × 3.5 + 6 = -6.25
The maximum depth, Cassidy went before coming back up to the surface =
= -6.25 ft = 6.25 ft. below the surface of the water.