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2006-08-09 12:14:30 · 8 answers · asked by billyjon1 2 in Science & Mathematics Mathematics

8 answers

This function does not have an inverse because it is not a 1-to-1 function. Only 1-to-1 functions have an inverse.

A function, f(x) is a 1-to-1 function if for every unique value of x produces a unique value for f(x). In other words, if two different values for x result in the same value for f(x), the function is not a 1-to-1 function. In the case of your function, f(x) = f(-x) (e.g., f(1) = f(-1) = 3; f(2) = f(-2) = 5, etc.), so it is obviously not a 1-to-1 function.

2006-08-09 12:26:18 · answer #1 · answered by hfshaw 7 · 1 1

If we let f(x) = x² + 2 and the inverse of the function be g, then you have to find g such that f(g) = x. In other words:

x = g² + 2
g = ±(x - 2)^½

You can see that g is not a function because it is a parabola opening horizontally so it fails the vertical line test. The inverse of the function, g, is a relation rather than a function.

You can say that there is no inverse function because the inverse of f(x) is not a function.

2006-08-09 19:28:51 · answer #2 · answered by pingu2me 1 · 1 0

y= x^2 +2
write x = y^2 + 2 (by replacing x with y and y with x)
Therefore y^2 = x - 2
or y = plus or minus square root of (x-2). It the inverse of the given function

2006-08-09 19:27:20 · answer #3 · answered by Amar Soni 7 · 0 1

y= 1/(x^2+2)

2006-08-09 19:33:32 · answer #4 · answered by Dallas M 2 · 0 1

You'll have to approach this problem as follows:
y-2 = x ^ 2 (Subtract 2 from both sides)
+-sqrt(y-2)=x (Find square root of both sides)
y=+-sqrt(x-2) (Replace x by y and y by x)

Note sqrt is the square root and +- is plus or minus.

2006-08-09 19:23:03 · answer #5 · answered by Anonymous · 0 1

technically, there is no inverse to this function, because it's not one-to-one

2006-08-09 19:21:28 · answer #6 · answered by f21ck 3 · 1 1

y = x^2 + 2
x = y^2 + 2
x - 2 = y^2
y = sqrt(x - 2)

y^-1 = sqrt(x - 2)

2006-08-09 19:24:55 · answer #7 · answered by Sherman81 6 · 0 1

y = +- sqrt (x-2)
that's y = plus minus sqrt (x-2)

2006-08-09 19:24:08 · answer #8 · answered by knuckle curve 1 · 0 1

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