WiseOlMoosey
How would I find the domain and range of (2)/(x^2-2x-3)? Is the domain x=-1 x=3
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cwrw238
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try factoring the denominator
what values of x are not possible?
WiseOlMoosey
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x=-1 and x=3
cwrw238
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the domain is all possible values of x
cwrw238
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right
cwrw238
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so -1 and 3 are not in the domain
mathstudent55
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The domain is the values that x can have.
y = 2/(x^2 - 2x - 3)
has a denominator. Since division by zero is not allowed, you need to find which values of x would make the denominator zero. To do that, solve (which you did)
x^2 - 2x - 3 = 0
(x - 3)(x + 1) = 0
x = 3 or x = -1
These are the value of x that must be excluded from the domain, so the domain is all real numbers except x = 3 and x = -1.
WiseOlMoosey
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oh so all reals except x=-1 and x=3 for the domain
cwrw238
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yup
WiseOlMoosey
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ok thanks! but what about the range?
cwrw238
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the range is all possible values of f(x)
cwrw238
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so can you figure that out?
WiseOlMoosey
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um how would i set it up?
WiseOlMoosey
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dang ok.. don't solve it for me but how would i go about that?
cwrw238
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well for a start the values of f(x) corresponding to x=3 or -1 will be excluded
WiseOlMoosey
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Couldn't I find the inverse of the function and then find the domain?
WiseOlMoosey
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@cwrw238
cwrw238
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yes the inverse of the function has domain which equals range of the function
WiseOlMoosey
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ok thanks for your time and patience!
cwrw238
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yw