I am practicing online with calculus problems my teacher linked me to for my test tomorrow, and one of the limit questions comes out to 1/12, but I'm getting 12 instead.
As X -> 6 , find the limit of X-6/(x^2-36)
I factor the denominator to (x+6)(x-6). I cancel the (x-6) in the numerator and denominator and I'm left with x+6. I then plug in 6, to get a limit of 12. I graphed to check, and this also makes sense when I look at the graph. But it tells me I'm wrong, and that the answer is 1/12, which doesn't make sense to me at all.
As X -> 6 , find the limit of X-6/(x^2-36)
I factor the denominator to (x+6)(x-6). I cancel the (x-6) in the numerator and denominator and I'm left with x+6. I then plug in 6, to get a limit of 12. I graphed to check, and this also makes sense when I look at the graph. But it tells me I'm wrong, and that the answer is 1/12, which doesn't make sense to me at all.
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The place where you went astray is that x+6 is the denominator, not the numerator.
(x-6) / (x^2 - 36)
= (x-6) / [(x-6)(x+6)]
= 1 / (x+6)
which approaches 1/12
(x-6) / (x^2 - 36)
= (x-6) / [(x-6)(x+6)]
= 1 / (x+6)
which approaches 1/12