The given graph is for a piecewise function consisting of two intervals:
(1) x ≤ 1 ⇒⇒⇒ the graph in this interval like <u>a cubic </u>function.
(2) x > 1 ⇒⇒⇒ the graph in this interval like <u>a quadratic </u>function
By comparing to the given options
<u>The answer is option c.</u>
Use the distance formula to find the distance between two points.

Answer:
The total volume of the water in the tank after 20 minutes = 1220 gallons
Step-by-step explanation:
Rate of water pumped into the tank r (t) = 30 (1 -
)
Initial volume of water in the tank = 800 gallons
The water in the tank after 20 minutes = Initial volume of water in the tank + Volume of water being pumped in the tank

= 
Where a = 0 , b = 20
Put the value of r (t) in above equation we get
= 
= ![30 [ t + \frac{e^{-0.16t} }{0.16} ]](https://tex.z-dn.net/?f=30%20%5B%20t%20%2B%20%5Cfrac%7Be%5E%7B-0.16t%7D%20%7D%7B0.16%7D%20%5D)
= 
= 420 gallon
Now, total volume in the tank



Therefore the total volume of the water in the tank after 20 minutes = 1220 gallons
Answer:
cos(a + b) = 
Step-by-step explanation:
cos(a + b) = cos(a).cos(b) - sin(a).sin(b) [Identity]
cos(a) = 
cos(b) = 
Since, terminal side of angle 'a' lies in quadrant 3, sine of angle 'a' will be negative.
sin(a) =
[Since, sin(a) =
]
= 
= 
Similarly, terminal side of angle 'b' lies in quadrant 2, sine of angle 'b' will be negative.
sin(b) =
= 
= 
By substituting these values in the identity,
cos(a + b) = 
= 
= 
= 
Therefore, cos(a + b) = 