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
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answer #1
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answered by hfshaw 7
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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
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answer #2
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answered by pingu2me 1
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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
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answer #3
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answered by Amar Soni 7
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y= 1/(x^2+2)
2006-08-09 19:33:32
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answer #4
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answered by Dallas M 2
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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
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answer #5
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answered by Anonymous
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technically, there is no inverse to this function, because it's not one-to-one
2006-08-09 19:21:28
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answer #6
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answered by f21ck 3
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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
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answer #7
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answered by Sherman81 6
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y = +- sqrt (x-2)
that's y = plus minus sqrt (x-2)
2006-08-09 19:24:08
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answer #8
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answered by knuckle curve 1
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