f/g(x) = (x^2 +6)
----------
(2x^2-5)

The Domain = ALL REAL NUMBERS - {2values}
what are these 2 values?
____ (smaller value)
____ (larger value)

Question

f/g(x) = (x^2 +6)
            ----------
               (2x^2-5)

The Domain = ALL REAL NUMBERS - {2values}
what are these 2 values?
____ (smaller value)
____ (larger value)

anonymous · Answer

So we are dividing two expressions, but when dividing, you want to make sure you dont divide by 0, because thats a math sin.

anonymous · Answer

i orginally thought the answers were 0 and 5

anonymous · Answer

So lets set the bottom polynomial equal to zero and solve for x:
$$2x^{2} - 5 = 0 \Leftrightarrow 2x^{2} = 5\Leftrightarrow x^{2} = \frac{5}{2}\Leftrightarrow x = \pm \sqrt{\frac{5}{2}}$$

anonymous · Answer

0 and 5 are ok to plug into the funtion, because:
$$2(0)^{2}-5 = 0-5 = -5$$
and
$$2(5)^{2}-5 = 50-5 = 45$$
We wouldnt be dividing by 0 in those cases, so the division is ok, thats why 0 and 5 arent the answer

anonymous · Answer

ohhh ok

anonymous · Answer

Basically, the rule is this: If you want to see what numbers to exclude from your domain, set the denominator equal to 0 and solve :)

anonymous · Answer

thank you! that makes it easier