PLATO:
can somebody please help me;
For which function is f(x) equal to f-1(x)?
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Answer:
C.) x = (y+1)/(y-1)
xy-x = y + 1
xy - y) = x + 1
y(x-1) = x+1
y = (x+1)/(x-1) ⇐ this is f-1(x) and it's identical to f(x).