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# Question on C4 Marking

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1. Hello, I was doing a Solomon Press Paper for C4 a few minutes ago and I stumbled upon a question asking me to find the inverse function. [The question is below]

f(x)= (2x-1)/(x-1)
For the inverse function I got (1-x)/(2-x) whereas the marking criteria says the answer is (x-1)/(x-2).

Would this be a problem in the actual exam or is it fine?

Thank you for any answers.
2. (Original post by RSharma98)
Hello, I was doing a Solomon Press Paper for C4 a few minutes ago and I stumbled upon a question asking me to find the inverse function. [The question is below]

f(x)= (2x-1)/(x-1)
For the inverse function I got (1-x)/(2-x) whereas the marking criteria says the answer is (x-1)/(x-2).

Would this be a problem in the actual exam or is it fine?

Thank you for any answers.
They're identical so it's fine.
3. It's the same answer because if you think about it, just sub in any number for x, so for example x=5

Using your answer you'd get - 4/-3, which is ultimately 4/3. If you used their answer, you'd get to 4/3 straight away. So either way it is correct

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