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Easy - Math - INVERSES - NEED ASAP PLEASE AND THANK YOU VERY MUCH!

Check my answers for two problems and do one for me - please and thank you! Just reassure me that they are right and if im wrong tell me what i did!

Easy - Math - INVERSES - NEED ASAP PLEASE AND THANK YOU VERY MUCH! Check my answers-example-1
Easy - Math - INVERSES - NEED ASAP PLEASE AND THANK YOU VERY MUCH! Check my answers-example-1
Easy - Math - INVERSES - NEED ASAP PLEASE AND THANK YOU VERY MUCH! Check my answers-example-2
Easy - Math - INVERSES - NEED ASAP PLEASE AND THANK YOU VERY MUCH! Check my answers-example-3

1 Answer

5 votes

Answer:

Part 1) No

Part 2) Option 4.
f^(-1)(x)=-(1)/(3)x+3

part 3)
f^(-1)(9)=4

Explanation:

Part 1) we have


f(x)=8x-3


g(x)=(x+8)/3

Find the inverse of f(x) and then compare with g(x)

Let

y=f(x)


y=8x-3

Exchange the variables x for y and y for x


x=8y-3

Isolate the variable y


8y=(x+3)


y=(x+3)/8

Let


f^(-1)(x)=y


f^(-1)(x)=(x+3)/8

therefore

the functions f(x) and g(x) are not inverses of each other

Part 2) we have


f(x)=-3x+9

Let

y=f(x)


y=-3x+9

Exchange the variables x for y and y for x


x=-3y+9

Isolate the variable y


3y=-x+9


y=(-x+9)/3

Let


f^(-1)(x)=y


f^(-1)(x)=(-x+9)/3


f^(-1)(x)=-(1)/(3)x+3

Part 3) we know that

For
x=4,
f(x)=9

so

For
x=9,
f^(-1)(9)=4