SOLUTION: What's the domain and range of and show me how to get it 1)x(r)=3r^2-6+12 2)y=1/x-4 3)b(x)=7/-x^2

Algebra.Com
Question 988697: What's the domain and range of and show me how to get it
1)x(r)=3r^2-6+12
2)y=1/x-4
3)b(x)=7/-x^2

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
I assume the first one is 3r^2-6R+12
at r=0 y=12
The vertex is -b/2a; r=1, from -(-6/6) That is the smallest value y will reach.
at r=1; y=3-6+12=9.
r has no bounds. Domain is all reals. Range is r> or equal to 9

========
second can be done by graphing.

Domain is all x except x=0. Range is all y except y=4.
Note, if the problem is y=1/(x-4), I will just show the graph. It shifts it, but you get the same type of answer, only shifted.

---------
7/-x^2
x can be anything but zero
x^2 can never be negative, and -x^2 therefore can never be positive. The range is y (-oo,0). Y can never equal zero but approaches it asymptotically,


RELATED QUESTIONS

These are my questions, and thank you very much for your help. 1) What is the slope of a (answered by Alan3354)
Hi. can someone please help me with this question? given y=√x-4-2,determine: a.... (answered by MathLover1,Alan3354)
Tell what you must do the first inequality in order to get second. Be sure to list all... (answered by sdmmadam@yahoo.com)
give the domain and range of the following linear and quadratic functions to show this: (answered by Boreal)
What is the domain and range of this equation:... (answered by scott8148)
this question asks to: "Find the domain and range of each function": 1.) y=x-1 2.)... (answered by Nate)
Can someone show me how to do this...please show your work :) 1/4x+1/4y=-1 x-y=8... (answered by vidhyak)
what is the domain and range of 3y(x-2)(x-1)=4(2x-3)? (answered by ewatrrr)
Find the domain and range of the function f={(x,x^2/1+x^2):x belongs to... (answered by Fombitz)