consider the function f(x)= x-2/x^2-81. for what value of x, if any, will this function a) equal 0? b) be undefined
explain.
f(x)= (x-2)/(x^2-81)
which is
(x-2)/ [ (x-9)(x+9) ]
it is zero if the numerator is zero
so when x = 2
it is undefined when the denominator is zero
x = 9 or x = -9
