In two or more complete sentences, explain how to use ordered pairs of points in f(x) = 2x + 5 and g(x)= x-5/2 to determine if f(x) and g(x) are inverses of each other. PLEASE EXPLAIN!

Respuesta :

You would do f(1)=2(1)=5, and g(1)=1-5/2. Then, you would compare the answers of both equations, after doing x=1, x=2, and x=3.

Answer:

f(x) and g(x) are inverse of each other.

Step-by-step explanation:

Given : Ordered pairs of points [tex]f(x)=2x+5[/tex] and [tex]g(x)=\frac{x-5}{2}[/tex]

To find : Determine if f(x) and g(x) are inverses of each other ?

Solution :

To determine f(x) and g(x) are inverse of each other then (fog)(x)=(gof)(x)

[tex]f(x)=2x+5[/tex] and [tex]g(x)=\frac{x-5}{2}[/tex]

LHS, [tex](fog)(x)=f(g(x))[/tex]

[tex](fog)(x)=f(\frac{x-5}{2})[/tex]

[tex](fog)(x)=2(\frac{x-5}{2}))+5[/tex]

[tex](fog)(x)=x-5+5[/tex]

[tex](fog)(x)=x[/tex]

RHS, [tex](gof)(x)=g(f(x))[/tex]

[tex](gof)(x)=g(2x+5)[/tex]

[tex](gof)(x)=\frac{(2x+5)-5}{2}[/tex]

[tex](gof)(x)=\frac{2x}{2}[/tex]

[tex](gof)(x)=x[/tex]

LHS=RHS

Therefore, f(x) and g(x) are inverse of each other.