Answer:
f (
x
) −
1 =
(
1/
4 x
) −
2.
Step-by-step explanation:
For inverse function, the x and y interchanges and then make y the subject again of the equation. See the working out below:
f (
x
) = 4
x + 8
f (
x
) = y
y = 4
x + 8
x = 4
y +
8 ----- interchanging y and x
Now make y the subject of the equation:
x = 4
y + 8
−
4
y = -
x + 8
y = (
−
1/
4 )
. − x
+ (
−
1/
4 ) .8
y = (
1/
4 x
) −
2
So the inverse function is:
f (x) −
1 = (
1/
4 x
) −
2
<h2><u><em>
Ans</em></u>wer:
</h2>
Assuming he works at a constant rate, the daily rate Mark rakes lawns in the fall is 40% of the daily rate he mows lawns in the summer.
<h2><u><em>
Step-by-step explanation:
</em></u></h2>
Fall:
5 neighbors' lawns / 2.5 hours = 2 lawns per hour
Summer:
6 neighbours' lawns / 1.2 hours = 5 lawns per hour
2 x 100% / 5 = 40%
2 is 40% of 5
Answer:
f(x) = 3x² - 15x + 12
Step-by-step explanation:
Given f(x) has roots x = a and x = b, then
(x - a) and (x - b) are the factors
f(x) is then the product of the factors
f(x) = a(x - a)(x - b) ← where a is a multiplier
Given roots are x = 4 and x = 1, then
(x - 4) and (x - 1) are the factors
With a = 3, then
f(x) = 3(x - 4)(x - 1) ← expand factors using FOIL
= 3(x² - 5x + 4) ← distribute
= 3x² - 15x + 12