PLEASE HELP ASAP 25 PTS + BRAIANLIEST TO RIGHT/BEST ANSWER
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Replace f(x) with y:
y = x^2 -1
swap the variables:
x = y^2 -1
Solve for y:
Add 1 to each side:
y^2 = x+1
Take the square root of both sides:
y = √(x+1)
To complete the solution use both the positive and negative values.
f^-1(x) = +/+√(x+1)
The last answer is the right one.
Answer:
f^-1(x) = ±sqrt(x+1)
Step-by-step explanation:
f(x) = x^2 -1
To find the inverse, exchange x and y and then solve for y
y = x^2 -1
Exchange x and y
x = y^2 -1
Add 1 to each side
x+1 = y^2
Take the square root of each side
±sqrt(x+1) = sqrt(y^2)
±sqrt(x+1) = y
f^-1(x) = ±sqrt(x+1)