Given the function f (x) = 3x, find the value of f-1 (81).
For this case, the first thing you should do is rewrite the function.
We have then:
y = 3 ^ x
From here, we clear the value of x:
log3 (y) = log3 (3 ^ x)
log3 (y) = x
Then, we rewrite the function again:
f (x) ^ - 1 = log3 (x)
Now, we evaluate the inverse function for x = 81:
f (81) ^ - 1 = log3 (81)
f (x) ^ - 1 = 4
Answer:
the value of f-1 (81) is:
f (x) ^ - 1 = 4
I am big pp lol xD hxyjdrh
Amount charged for downloading individual songs = x dollars
Amount charged for downloading an entire album = y dollars
In respect to person A:
6x + 2y = 25.92
3x + y = 12.96
y = 12.96 - 3x
In respect to person B:
4x + 3y = 33.93
Putting the value of y from the first equation in the second, we get
4x + 3(12.96 - 3x) = 33.93
4x + 38.88 - 9x = 33.93
- 5x = - 4.95
x = 0.99 dollars
Putting the value of x in the first equation, we get
y = 12.96 - 3x
= 12.96 - 2.97
= 9.99 dollars
10
1240 x 10 = 12400
12400 = 12400
