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anonymous
 5 years ago
Domain and range of x^2+7x+12(its all under the square root)
anonymous
 5 years ago
Domain and range of x^2+7x+12(its all under the square root)

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[f(x)=\sqrt{x^2 + 7x + 12} \rightarrow \text{f(x) is defined }\forall x\text{  }x^2 + 7x + 12 > 0\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0am new to this,that is how i meant it :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Right, so the function is defined so long as the stuff under the radical is greater than or equal to 0. So solve the quadratic and see where it equals 0 and where it's above/below. That will tell you what x values are ok.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sounds right.. so (x+4)(x+3) So when will this be negative?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Remember that a product is negative only when it has an odd number of negative factors.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so my domain is 4>= x >= 3 ?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0When x is very large and negative what will that product be?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[(\infty + 4)(\infty+3) = ? \]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0If you put in a value (any value in between 3 and 4, let's say 3.5 the result will be an imaginary number. The ABSOLUTE VALUE of X must be greater than 3 OR greater than 4. That means any number in between 3 or 4 must be excluded! (inf, 3] U [4, +inf).

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The domain is (inf, 3] U [4, +inf).

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0my brain is a bit fried from java programming last week

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0God, I don't know what is wrong with me today. The range is (inf, 3] U [4, +inf). The domain is X.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0If you have a function y=f(x), x is the domain and y is the range.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Imagine two sets. set D={A,B,C} and set R={3,5,7}. If some function "f" associates the letter A with the number 3, then f(A) =3 and A is in the Domain of f and 3 is in the range of f. Did that make any sense to you?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok cool, am good in math , not really in domain and range but thanks

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I understand totally. It took me a long, long time to understand the concept of domain and range. If you have the time find " Schaum's Outline Series: Theory and Problems of Set Theory and Related Topics" by Seymour Lipschutz and read page 45. It will explain everything you never wanted to know about Range and Domain and didn't know who to ask. LOL.
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