Question

Identify the domain and the range of the following 1.y=3x^2-x+1 2. y= /x+4/

Answer 1

@ganeshie8 pls help again sir

Answer 2

@amistre64 pls help sir

Answer 3

the domain consist of all valid inputs; we can assume the set of Reals and then weed out any known errors such as a divide by zero, negative even roots, logs of 0 and less .... those types of things.

Answer 4

polynomials have a domain of all Real numbers, its when we get into ration expressions and such that we have to restrict the domain

Answer 5

the range is the set of all the output values ... think of it as the set of all y values. think of the lowest and highest values the expression can give us

Answer 6

lets start with no. 1 :)

Answer 7

k, what can you tell me about how the shape of it will look

Answer 8

uhm it doesnt have a shape

Answer 9

it does have a shape if we graph it ....

im assuming you want to know the range, or is the domain still an issue for you?

Answer 10

i want to know both of them :)

Answer 11

look at the places that have an x, do any of them require us to restrict the values of x that we use?

Answer 12

3 x^2; is there any value of x that we cannot use in this?

-x; is there any value of x that we cannot use in this?

Answer 13

@amistre64 slr i went to the kitchen and cook food sorry :)

Answer 14

can you think of any values of x that we would not be bale to use in this setup?

things to look for are dividing by zero, taking the even root of a negative value, or taking the log of anything 0 or negative.

Answer 15

i really dont know maybe -1?

Answer 16

since there are no logs, sqrt, or division involved .... its a safe bet to say that there are no restrictions to be made.

Answer 17

oh ok

Answer 18

now, as for the range, you claim there is not shape to these things, so we would have to resort to calculus techniques to determine low and high spots .... are you taking calculus classes?

Answer 19

uhm no, im just in 2nd year high school

Answer 20

then they most likely have been trying to teach you that equations produce graphs, and how to relate certain properties of equations to their basic graph shapes.

Answer 21

yes

Answer 22

can you tell me the name of an equation whose highest degree is x^2 ? what properties do you know about this general graph/equation?

Answer 23

they didin't teach that yet it's only the 1st week of our class and the teacher mde this kind of assignment

Answer 24

it takes chapters in a textbook to cover this stuff. if you do not have these foundational concepts to work with, i dont see a way to proceed towards a solution at the moment. At least nothing that i have the spare time for.