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For questions 5&6 find F -1(x), the inverse of F(x)

For questions 5&6 find F -1(x), the inverse of F(x)-example-1
User Emmeowzing
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1 Answer

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To find the inverse function, we can follow the next steps:

First Function

1. Replace x with y as follows:


y=3x+7\Rightarrow x=3y+7

2. Solve the resulting equation for y. Subtract 7 from both sides of the equation:


x-7=3y+7-7\Rightarrow x-7=3y

3. Divide both sides of the equation by 3:


((x-7))/(3)=(3)/(3)y\Rightarrow y=((x-7))/(3)=(1)/(3)(x-7)=(x)/(3)-(7)/(3)Second Function

We need to repeat the process to obtain the inverse of this function:

1. Replace x with y:


y=8x\Rightarrow x=8y

2. Solve for y. Divide both sides by 8:


(x)/(8)=(8)/(8)y\Rightarrow y=(x)/(8)

In summary, we have that the inverse functions are:

For function


y=3x+7

The inverse function is:


y=F^(-1)^{}(x)=((x-7))/(3)

And, for the function


y=8x

The inverse function is:


y=f^(-1)(x)=(1)/(8)x

User Saurabh Rajpal
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