Hola! another math question... hope you can help me, i badly need your help, help me solve?

Question

The given function f is one-to-one.
f^-1(x) = (ax+b)/(cx+d)
find f^-1

These are the choices guyz...
a. f^-1(x) = -(dx+b)/(cx-a)
b. f^-1(x) = -(dx+c)/(cx-b)
c. f^-1(x) = (dx+b)/(cx-a)
d. f^-1(x) = (dx+c)/(cx-b)

THANKS ALOT!

oh i am sorry, it supposed to be f(x) = (ax+b)/(cx+d)

Answer 1

f(x) = (ax + b)/(cx + d)

y = (ax + b)/(cx + d)
x = (ay + b)/(cy + d)
xcy + xd = ay + b
xcy - ay = -xd + b

y(xc - a) = -xd + b
y = (-dx + b)/(cx - a)
y = (-(dx - b))/(cx - a)

f^-1(x) = (-(dx - b))/(cx - a)

You don't have the answer listed.

Answer 2

y = (ax+b)/(cx+d)
Switch x with y
x = (ay+b)/(cy+d)
Solve for y.
Multiply both sides by cy+d
x(cy+d) = ay+b
Distribute the x on the LHS
cxy + dx = ay + b
Bring the terms involving y to one side and the terms NOT involving y to the opposite side.
cxy - ay = b - dx
Factor y on the LHS
y(cx-a) = b - dx
Divide both sides by cx-a
y = (b-dx)/(cx-a)
y = (-dx+b)/(cx-a)
This looks similar to choice a, but it is not the same as a.
Do you have everything typed correctly?
Note: You can immediately elliminate choices b and d because they do not have an a in the answer. The letter a will not disappear when finding the inverse.

Answer 3

I'm sorry but are you looking for the inverse function..because your original function is already written as a inverse function. Please clarify.

Answer 4

find f^-1??? youre missing something

Answer 5

i choose E

Answer 6

D