Answer:
f⁻¹(7) = 1
Step-by-step explanation:
Step 1: Write out function
f(x) = 3x + 4
Step 2: Find f⁻¹(x) (or known as inverse f(x))
y = 3x + 4
x = 3y + 4
-3y + x = 4
-3y = 4 - x
y = -4/3 + x/3
Step 3: Plug in 7 into inverse f(x)
f⁻¹(7) = 7/3 - 4/3
f⁻¹(7) = 3/3
f⁻¹(7) = 1
Question 21
Selling price = 18 + 18 x 36/100
Question 22
Discount price = 80 - 80x10/100
Selling price = discount price + discount price x 7/100
Answer:
1. The speed of the truck, S = D/T.
2. The formula that connects D and T is: S = D/T.
3. The coefficient of variation, k, is the ratio of the standard deviation to the mean speed.
Step-by-step explanation:
a) The speed of a truck at a fixed speed is given as the distance covered by the truck divided by the time it takes the truck to cover the said distance. This implies that speed is a function of distance and time. However, this formula represents the mean speed. There are variations in speed.
b) If the truck covers a distance of 60 kilometers, for example, under 3 hours, we can conclude that the speed is 20 kilometers per hour (60/3) or 20 km/hr.
No, it is not. Because it doesn't satisfy the first equation.