Question 179640
You can graph the functions and look for regions that go from {{{infinity}}} to {{{-infinity}}} or vice versa.
These specific functions are discontinuous (undefined) any time the denominator goes to zero.
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b)At x=0.
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{{{ graph( 300, 300, -5, 5, -10, 10, (7x-4)/x) }}}
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c)At x=0.
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{{{ graph( 300, 300, -5, 5, -10, 10, ((x^2)-1)/x^3
) }}}
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d) When x^2+x-6=0,
{{{x^2+x-6=0}}}
{{{(x+3)(x-2)=0}}}
At x=-3 and at x-2.
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{{{ graph( 300, 300, -5, 5, -10, 10, (13x)/((x^2)+x-6))
 }}}
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