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Determine whether each pair of functions are inverse functions. 1) f(x) = 8x – 10, g(x) = (x + 10) 2) f(x) = 4x + 5, g(x) = 4x – 5

Respuesta :

Answer:

Step-by-step explanation:

To find the inverse of a function you take it in y=f(x) form, switch x and y and then solve for the new y.

So I'll do the first one.

f(x) = 8x-10

y=8x-10 Now switch x and y

x = 8y-10 Now solve for y.  

x+10=8y

(x+10)/8 = y

g(x) is not that, so it is not the inverse.  Can you figure out the second one?

Answer:

Both are not inverse functions.

Step-by-step explanation:

To find : Determine whether each pair of functions are inverse functions ?

Solution :

To determine the functions has to satisfy the condition,

[tex]f(g(x))=x=g(f(x))[/tex]

1) [tex]f(x) = 8x-10,\  g(x) = (x + 10)[/tex]

[tex]f(g(x))=f(x+10)[/tex]

[tex]f(g(x))=8(x+10)-10[/tex]

[tex]f(g(x))=8x+80-10[/tex]

[tex]f(g(x))=8x+70[/tex]

As [tex]f(g(x))\neq x[/tex]

[tex]g(f(x))=g(8x-10)[/tex]

[tex]g(f(x))=8x-10+10[/tex]

[tex]g(f(x))=8x[/tex]

As the condition is not satisfied.

2) [tex]f(x) =4x+5,\  g(x) =4x-5[/tex]

[tex]f(g(x))=f(4x-5)[/tex]

[tex]f(g(x))=4(4x-5)+5[/tex]

[tex]f(g(x))=16x-20+5[/tex]

[tex]f(g(x))=16x-15[/tex]

As [tex]f(g(x))\neq x[/tex]

[tex]g(f(x))=g(4x+5)[/tex]

[tex]g(f(x))=4(4x+5)-5[/tex]

[tex]g(f(x))=16x+20-5[/tex]

[tex]g(f(x))=16x+15[/tex]

As the condition is not satisfied.

Both are not inverse functions.