# Limit problem (1 Viewer)

### Users Who Are Viewing This Thread (Users: 0, Guests: 1)

#### screamtrumpet

1. The problem statement, all variables and given/known data

lim t^2-9/t-3
x>3
2. Relevant equations

3. The attempt at a solution

I factored it into (t-3)(t+3)/(t-3)
i then cancelled out the (t-3)'s and substituted 3 to get 6 is this correct?

#### rakalakalili

Assuming you made a typo and your problem is the limit as t -> 3, then yes, what you did is correct. You can only ever cancel an expression with a variable (such as (t-3)) if you are sure that it is not going to be zero. In this case, we are taking the limit as t goes to 3, so (t-3) is never actually equal to 0. Thus, we can cancel (t-3) and you are correct.

Thanks!

### The Physics Forums Way

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving