find values of x, if any, which f is not continuous.

Question

1. f(x)= x+2/x²-4
2. f(x)= x/2x²+x
3. f(x)= 3/x + x-1/x²-1
4. f(x)= 5/x +2x/x+4

Answer 1

For all of these, just set the denominator(s) to zero and solve for x. For example, for #3, there are 2 denominators.

x=0

x²-1=0 --> x = ±1

So the values of x=0,-1,1 will make the equation noncontinuous.