Question

Which two functions are inverses of each other?
Of(x) = x, g(x) = -x
of(x) = 2x, g(x) = -X
f(x) = 4x, 8(x) = x
O Mx) = -8x, 8(x) = 8x

Answer 1

Inverse is the opposite.

A negative value is an inverse of the same positive value and a positive value is an inverse of the same negative value.

Examples:

-2 is the inverse of 2

5 is the inverse of -5

The answer is:

f(x) = x, g(x) = -x

f(x) = -8x, g(x) = 8x

Answer 2

Answer:

Option 3

Step-by-step explanation:

We have to find, which two functions are inverses of each other?

Solution :

Two functions are inverse when the condition is fulfilled,

f(g(x))=x=g(f(x))

Applying in all options,

1) f(x)= x, g(x) = -x  

$f(g(x))=f(-x)=-x\neq x$

Not true.

2) f(x)= 2x, g(x) = -\frac{1}{2}x

$f(g(x))=f(-\frac{1}{2}x)=2\times(-\frac{1}{2}x)=-x\neq x$

Not true.

3) f(x)= 4x, $g(x) = \frac{1}{4}x$

$f(g(x))=f(\frac{1}{4}x)=4\times(\frac{1}{4}x)=x$

$g(f(x))=f(4x)=\frac{1}{4}\times 4x=x$

i.e. f(g(x))=x=g(f(x)) is true.

So, These two functions are inverse of each other.

4) f(x)= -8x, g(x) =8x

$f(g(x))=f(8x)=8\times(-8x)=-64x\neq x$

Not true.

Therefore, Option 3 is correct.