Question

For what the value of x, the following expressions become undefined? :

1)x²-y/x-y
2)x³/x²-4
3)5x³/4-x
4)3x²-2xy/x²-16
5)x²-5x+6/x²-49

Please explain nicely^_^
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Answer 1

Not sure about 1 and 4, since there's also a y variable, but:

2) x=2

3) x=4

5) x=7

When we plug these values into the given equation, we get undefined values, such as something divided by 0.

if we use 2 as an example, we have (x³/x²-4)

If we replace 2, we get (2³/2²-4)

Which simplifies to 8/4-4

=8/0