







The inverse of y = x(x  2) 
20161221 

Sasha pose la question : Hello, I recently stumbled upon this question and I haven't been able to figure it out.
Why is the inverse of y=x(x2) not a function?
Suggest a domain restriction which would ensure that the inverse is a function.
Thank You :) Penny Nom lui répond. 





The domain and range of a function 
20160219 

Genius pose la question : State the domain and range
g(x)=x(x1) Penny Nom lui répond. 





The range of a function with a finite domain 
20160125 

Hannah pose la question : Solve y=(1⁄4)x1 if the domain is (4,2,0,2,4).
I don't get how to do this. Can anyone help? Penny Nom lui répond. 





The domain of cos2x/(sinx2) 
20151102 

Ameen pose la question : Find the domain of:
f(x) = cos2x/(sinx2) Penny Nom lui répond. 





A quadratic equation 
20131127 

corinanna pose la question : Hi,
How do you find a quadratic equation given the domain & range,
& or the yintercept? Penny Nom lui répond. 





The domain of a derivative 
20131010 

Renee pose la question : I am looking to find the domain of a derivative of a radical function,
one such as: f(x) = the square root of (8 − x).
I am kind of unclear on how domains work for derivative.
I don't understand how you take a function's domain and use that to
find the derivative's domain.
Thanks! Penny Nom lui répond. 





What is the domain of f(x)=sin(ln(x))/ln(x)? 
20130206 

Behrooz pose la question : Hi, the following problem may be interesting:
What is the domain of f(x)=sin(ln(x))/ln(x)?
Be careful, domain is not obvious.
Best regards
Behrooz Penny Nom lui répond. 





Domain and range 
20120809 

Lucy pose la question : Can two different functions have the same domain and range? Why or why not? Penny Nom lui répond. 





The domain of a function 
20110508 

Minks pose la question : (x^2 + 1 / x^2 +2x  3 ) X ( x^2 9 / x^2  2x  3) Penny Nom lui répond. 





Log[f(x)] 
20100308 

sourabh pose la question : What is the number of solutions of the equation
9 x 2  18 x + 5 = 0 for x, such that the expression
log10[(x+1)(x+2)] exists? Harley Weston lui répond. 





The domain, range and inverse of a relation 
20100108 

Nazrul pose la question : Given that A={2,1,0,1,2}, S={(x,y): x belongs to A, y belongs to A and y^2=x}. How can I find the domain and range of the relation S. What is the inverse relation of S. Please show me the process in details.
Thank you. Penny Nom lui répond. 





y = sin(x) + 3 
20091110 

Kapilan pose la question : When graphing trigonometric functions like SIN and COSINE does f(x)=x
squared equal to SIN or COSINE
Also what is the range, domain, period and ampliltude for y=sin@ + 3 Harley Weston lui répond. 





Domain and range 
20090911 

Aubrey pose la question : I'm supposed to "state the domain/range of each of the following relations" and it's totally not making sense...
Examples:
{(x,y) : x = square root of y}
{(x,y) : y = x + 1, x is some even integer}
Thanks in advance!!
Aubrey Robert Dawson lui répond. 





Range and Domain of a Star 
20090514 

Larry pose la question : I am an old teacher trying to help my grandson. He has to draw a structure to scale and then determine the function, domain and range. One line on the structure is from (0,8) to (8,4). I used the intercept method and found the function to by y=1.5x +8 (I think) but can't find the range and domain) Thanks Janice Cotcher lui répond. 





What is the domain of the function (3x+4)/(x^2+5x+6)? 
20081215 

Robert pose la question : What is the domain of the function (3x+4)/x^2+5x+6 Harley Weston lui répond. 





Quadratic equations arising from practical problems 
20081124 

Lenval pose la question : Why do quadratic equations arising from practical problems often give physically impossible solutions such as negative distances, negative times or, say, a polygon with a negative number of sides? For example: "A river in flood carries a tree tsquared  23t metres downstream in t seconds. How long does it take for the tree to be carried 50 metres downstream?" This gives t=25 and t=2. Please explain the second 'solution', which is not physically possible. Chris Fisher and Victoria West lui répond. 





Domain and range 
20080916 

Cara pose la question : Please help me to find the domain and range of the following function:
F(x)=sin(2x) Harley Weston lui répond. 





What is the domain of (f/g)x? 
20080728 

Warren pose la question : If f(x)=3x5 and g(x) = square root of x5, what is the domain of (f/g)x? Penny Nom lui répond. 





Domain and range 
20080723 

Cane pose la question : Hi, my name is Cane and i am stuck on this problem. Find the doman and
range then graph.
y= square root of(x squared  6x) + Square root of(6x  x squared) Harley Weston lui répond. 





Domain & Range of a Periodic Function 
20080711 

Michelle pose la question : The depth, w metres, of water in a lake can be modelled by the function,
w=5sin(31.5n+63) +12 where n is the number of months since
January 1, 1995. Identify and explain the restrictions on the domain and
range of this function. Janice Cotcher lui répond. 





Domain and range 
20080707 

marylie pose la question : what is the domain and range of f(x)= sq.rootof x ^24??tnx Harley Weston lui répond. 





Two function problems 
20080410 

keith pose la question : find the domain: F(x)= 1/ {ln (x+5)  ln (7x)}
find the inverse: g(t)= sqrt {23 ln (1t)} Penny Nom lui répond. 





Composition of functions 
20080307 

sharon pose la question : Find FoG(x)
F(x)= the square root of x9
G(x)= x^2
and also find GoF and their domains Penny Nom lui répond. 





The range of a function 
20080210 

Rachel pose la question : How do I find the range of this function?
(3x^32x^2+6x7)/(x^23x4) Harley Weston lui répond. 





The domain and range of a function 
20080205 

Victoria pose la question : Please...Please...Please tell me how to find domain and range.
Every text and website i have gone to does not make any sense to me!
Below are two example problems i found on a website...
f(x) = (8x3)/(4x1)
and
y = 2x+1
Please explain step by step how to find the domain and range. Penny Nom lui répond. 





The range of a function 
20071112 

Camille pose la question : Hi There,
I am taking a calculus class by correspondence and part of the introduction is
learning how to find domain and range of functions. I understand how to find the
domain. I also understand that if you find the inverse of the equation and
solve for x to find the domain it will give you the range because the domain
of the inverse is equivalent to the range of the original equation. However when
trying to apply this method to complicated questions (ie: square root in the
denominator) I get confused and can't solve for x.
Camille Harley Weston lui répond. 





Domain and range 
20071012 

Dawn pose la question : Hi, I've been out of school for 8 years and recently picked up a math correspondence course. I'm having trouble trying to figure out the range and domain of a linear function. I've read everything I can find in my text, lessons and on your site and I still can't figure out what I'm suppose to be doing. The function is y=2x+1. Please help. Penny Nom lui répond. 





The domain and range of a quadratic function 
20070717 

Linda pose la question : I have been trying to solve this problem but I'm unable to figure it out. How do I find the domain and range of
y=(x+1)^23? Please explain...thanks! Stephen La Rocque and Penny Nom lui répond. 





Interval of the domain 
20070513 

Gale pose la question : What does the term interval of the domain mean? Penny Nom and Stephen La Rocque lui répond. 





Finding domains using number lines 
20070225 

Saher pose la question : Discuss domain of the function, f(x)= (x+1)(x2) / (x+3), with the entire thing under a square root.
I'm being taught how to find the domain using the number line. Our teacher says that there are 56 choices, but I get stuck somewhere around 2, and I don't know how to give my answers after I've obtained the first one, which seems to be (3, infinity). HELP!! Thank you Stephen La Rocque lui répond. 





Inputoutput table 
20070110 

Richard pose la question : Question is make an input  output table for the function using the domain 0,1,2,3,4, Then state the range of the function.
y =x + 8 ?
y =0.4x +3 ? Penny Nom lui répond. 





The domain of a function 
20061115 

April pose la question : Determine the domain of the function h(x) = 4x/x(x^249) Stephen La Rocque lui répond. 





Domain and range 
20060308 

Jennifer pose la question : How do I find the domain of x2y=1 if the range is {2,0,5,8} Penny Nom lui répond. 





The range of a function 
20050821 

Kelsey pose la question : What is the range of the function f(x) = 4x  6 when the domain is {3,1,1,3,5}? Penny Nom lui répond. 





Domain and range 
20040801 

JJ pose la question : I'm checking domain and ranges of these functions. Are these right? Penny Nom lui répond. 





Domain of a function 
20031014 

Karim pose la question : Find the Domain of the Function H(x) = Log3 (4x + 7)10 H(x) = log base 3 times 4X plus 7 minus 10 i am having problem solving these kinds of problems. Penny Nom lui répond. 





The domain of 1/g(x)  5 
20030703 

Barbara pose la question : If the range of g(x) is ( neg. infinity,4] and the domain of g(x) is ( neg. infinity, infinity), how do I find the domain of 1/g(x)  5? Penny Nom lui répond. 





Domain of a function 
20020720 

Andy pose la question : I'm having difficulty in finding the domain of 1/(x^{2} 2x + 4) one over x squared minus 2 x plus 4. Penny Nom lui répond. 





Functions and relations 
20020425 

Erin pose la question : Here's a few math problems that might drive a person insane ;)  If 2f(x)  3f(1/x) = x^2 what is f(2)?
 What are the domain and range of the following relations?
 x^2  4y^2 = 25
 4x^2 + 9y^2 = 36
 The port of Swan Harbor is 200km away from Merry Town Inlet on a bearing of N50E from Merry Town. A ship leaves Merry Town at 8am and sails N15W at 15 km/h. At the same time, a second ship leaves Swan Harbour on a course of S80W at 20km/hour. How close, to the nearest km, are the two ships at 13:00?
 Prove the identity. 1+sinx + cosx/ 1sinx + cosx = 1+sinx / cosx
Penny Nom lui répond. 





Composition of functions 
20020406 

Yvonne pose la question : In our new text book, the following question occurs: State the domain and range of g(f(x))given that f(x) = x^{2}  4 and g(x) = sqrt(x) The range of f(x), x<=4, is the domain of g(x). BUT, there is no solution in the Real numbers for g(f(x))= sqrt(x^{2}  4). In the solutions it says that this is not a function and therefore does not have a domain or range. Is it a relation? Is it anything? Claude Tardif lui répond. 





The domain of a function 
20010408 

Mina pose la question : Let f(x) = (2x^{2}+3x17)/(x+5) What is the domain of f? What are the values of x for which f'(x) does not = 0? Harley Weston lui répond. 





Domain and Range and Zeros 
20010227 

Beth pose la question : 1. f(x)=152xx^{2} 2. g(t)=square root of 4t^{2} 3. y=t3/t^{2}t6 Penny Nom lui répond. 





The domain of the derivative 
20010222 

Wayne pose la question : I know that the domain of f'(x) is a subset of the domain of f(x). Is it necessarily true that the subset will have at most one less element than the domain of the original function? Harley Wesston lui répond. 





Range of a function 
20001121 

David Bell pose la question : Given a rational function such as f(x) = (8x3)/(4x1). How can the range be found. Penny Nom lui répond. 





Domain of a function 
20001115 

Mickey pose la question : state any restrictions on the domain of the function. y = 5x  12 over 27x + 6 x does not equal what________? Penny Nom lui répond. 





An equation involving x to the x 
20000722 

Joy Peter pose la question : I am joy, a teacher teaching Maths at the secondary level and while solving a sum came to this stage when i got x^{x} (1 + log x) = 0, by which we can conclude that x^{x} = 0 or 1 + log x = 0. If x^{x} = 0, than what should be the value of x? I feel that the value of x should then be 0 (zero) but then how do I explain this to the students as we also know that anything to the power of 0 is 1 but here 0 raised to 0 is 1. If this is not defined then how do I explain this? Penny Nom lui répond. 





Domain of a function 
20000119 

Stacey Hutchison pose la question :
What is the domain of: f(x) = 1/(x + 4) Patrick Maidorn lui répond. 





Domain and Range of a Function 
19991114 

Michelle Mellott pose la question : How do you find the range of the following function: 2y^{2}/(y^{2}+5y+6)?? I know the domain is x not equalled to 2, 3. How can one easily find the range? Harley Weston lui répond. 





The Range of a Function. 
19970912 

Karel Marek pose la question : Math Is Book 6 (Ebos/Tuck) question 5(b) gives a surprising answer at the back of the book..The question is: Indicate the domain and range for this: y = sqr(x9) (Square root of) The answer for the domain is x>=9 which is not surprisingly, but the range is y>=0, yER ... which I could understand if you were not allowed to transform the equation into x as the subject.. But all example on the facing page DO TRANSFORM the equation at will with x and/or y as the subject.. Can you explain this... ?? Chris Fisher lui répond. 

