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Question 940091: for the indicated functions f and g, ﬁnd the
functions f + g, f - g, fg, and f|g, and ﬁnd their domains.
f(x)= 2x^2; g(x)= x^2 + 1

Click here to see answer by ewatrrr(24785)

Question 940159: i need help with problems 28 and 29. please include all work in the answers. here is a pic of the problems
http://imgur.com/KqTus5c
thanks in advance
Click here to see answer by brysca(112)

Question 940158: i need help with problem 38. please include all work in the answer. here is a pic of the problem
http://imgur.com/3xJFgr3
thanks in advance
Click here to see answer by MathLover1(20850)

Question 940596: Express the function y= sqrtx^2+5 as a composition y=f(g(x)) of two simpler functions y=f(u) and u=g(x).
I got g(x)= x^2+5 and f(x)= sqrtx

Click here to see answer by richard1234(7193)

Question 940735: x^3 - 9x
Click here to see answer by Fombitz(32388)

Question 940994: f(4.3)= the square root of x-4 divided by x^2-9
I have to give a radical as an answer, I cannot give a decimal.
PLEASE HELP, THANK YOU !!!
Click here to see answer by Fombitz(32388)

Question 941055: The function f:x->px+q, xER, is such that f^-1 (6)=3 and f^-1 (29)=-2.
Find f^-1 (27).
I have spent a long time trying to figure this out and I can't get it.
The answer given in the textbook is 6.
I have found the inverse function to be f^(-1): 1/p (x-q) so I am guessing that means I subtract or add something to x and then divide it.
Any help on this would be greatly appreciated.
Thanks
Click here to see answer by Fombitz(32388)

Question 940842: Determine whether the following equation defines y as a function of x
x-9=y^2
Click here to see answer by Fombitz(32388)

Question 941088: The function g is defined by g(x) = 1-2x, where x belongs to the real numbers.

Find the function
g^(-1)
The answer given in the textbook is:
x = 1/2(1-x)
I thought the answer would be 1 / (1-2x) but then how would that get to the answer given in the textbook?
Trying to work backwards from the answer 1/2(1-x) would become 1/2 - 1/2x but I can't see how that came about.
Any help given would be appreciated. Thanks.

Click here to see answer by richard1234(7193)

Question 941101: Which equation represents the inverse, f ^−1(x), of the function f(x) = 3x + 1?
Option A: f^-1 (x) = 1/3 x+1
Option B: f^-1 (x) 1/3 x-1
Option C: f^-1 (x) 1/3 x- 1/3
Option D: f^-1 (x) 1/3 x + 1/3
Click here to see answer by Fombitz(32388)

Question 941104: y= 7x - 8
x= 7
use the substitution method to solve the system of equations. enter your answer as an ordered pair
Click here to see answer by Fombitz(32388)

Question 941117: Does the table represent an expoential function?
x 1 2 3 4
y -1 -8 -27 -64
yes or no
Click here to see answer by Alan3354(69443)

Question 941146: Indicate whether A. or B.

__ 1. {(1, 4), (2, 5), (4, 7), (9, 12)} A. function
__ 2. {(4, 3), (17, 29), (18, 52), (4, 19)} B. not a function
Click here to see answer by Fombitz(32388)

Question 941256: Hello I found this equation on SAT question of the day January 22, 2015
If f(x) = x + ax , and 7/2 what is f(3/2)
I chose D which was wrong
I do not understand where the 9/2x came from when clicking the correct answer
Please help correct and educate me
Thank you
Click here to see answer by richard1234(7193)

Question 941314: True or false: if f is an odd function whose domain is the set of real numbers and a function g is defined by
g(x)={f(x) if x>=0, -f(x) if x<0,
then g is an even function. Explain your answer
Click here to see answer by Fombitz(32388)

Question 941364: I have 360 twenty five cent coins.How many dollars will I get in exchange for my coins.
Oliveruth01@gmail.com
Click here to see answer by Alan3354(69443)

Question 941424: Given the function f(x) = (2x-4)/x
and x belongs to the real numbers and x does not equal zero, find
f^2(x)
The answer given in the textbook is 4 / (2-x).
I can not understand how to get this answer.
I think f^2(x) = ff(x) but I don't know how to do this function.
Any help at all would be appreciated very much. I've spent over an hour trying to work this out.
Thanks
Click here to see answer by richard1234(7193)

Question 941453: chart which shows at least three ordered pairs for the function
y = x^2 - 2x + 2
Click here to see answer by TimothyLamb(4379)

Question 941453: chart which shows at least three ordered pairs for the function
y = x^2 - 2x + 2
Click here to see answer by MathTherapy(10552)

Question 941897: Which sets of ordered pairs are functions?
A = {(4,3),(17,29),(18,52),(4,19)}
B = {(19,4),(52,18),(29,17),(3,4)}
C = {69,82,44,87}
Click here to see answer by MathLover1(20850)

Question 941952: The owner of a grocery store finds that she can sell 2216 gallons of milk each week at $2.71 per gallon and 2296 gallons of milk each week when she offers a sale price of $2.51 per gallon. Assume that the number of gallons sold S is a linear function of the price p per gallon.
(a) Find a formula for the gallon sales, S(p), as a function of price p. (Don't include S in the answer box.)
(b) How many gallons would you expect to sell at $3.51 per gallon? (round to the nearest gallon)

Click here to see answer by josgarithmetic(39618)

Question 942025: What is the difference quotient of the equation f(x)=4/x?
Click here to see answer by jim_thompson5910(35256)

Question 942207: How do I put 3x+y=10 in function notation? Very confused...
Click here to see answer by richard1234(7193)

Question 942371: The function f defined by
f(x) = x^5+x^3
is one-to-one (here the domain of f is the set of real
numbers). Compute f^−1(y) for four different values of y of your choice.
[For this particular function, it is not possible to find a
formula for f^−1(y).]
Click here to see answer by richard1234(7193)

Question 942368: Consider the function h whose domain is the interval
[−3, 3], with h defined on this domain by the formula
h(x) = (3 + x)^2.
Does h have an inverse? If so, find it, along with its
domain and range. If not, explain why not.
Click here to see answer by josgarithmetic(39618)

Question 942363: Find f(x) and g(x) so that the function can be described as y = f(g(x)).
y = nine divided by x squared + 2
Click here to see answer by Theo(13342)

Question 942429: 1.)Is the interval [0,1] closed under multiplication. ? Is yes, why? If no, give explanation
2.)is the interval [0,1] closed under subtraction if yes or no why?
3.) what does it mean when a question says , is f (x) a function ?
4.) what does f(x) means?
I need your help I'm so confused

Click here to see answer by richard1234(7193)

Question 942508: Find (w�g)(1) for w(x)=14x^2-8x+4 and g(x)=8x+4
Click here to see answer by MathLover1(20850)

Question 942570: I'm unsure as to the answer given by BBC bitesize to one of their problems, the problem itself being f(x) = (x-1)/(x+1) find ff(x).
So I've gotten as far as (-2/(x+1)) * ((x+1)/(2x)) which equates to (according to me) -2x-2/2x^2+2x, now BBC show the answer to be 1/x which I do not get, however I think the answer is 1/x^2 (assuming that -x and x cancel eache other, which I'm also not entirely sure is allowed), so yeah that's my problem...
(Link to problem: http://www.bbc.co.uk/bitesize/higher/maths/algebra/functions/revision/3/)
Click here to see answer by stanbon(75887)

Question 942631: Find the domain of the function
f(x)= 2- 8/x4th power
Click here to see answer by stanbon(75887)

Question 942661: 7 2
- - - =
9 9

7 over 9 minus 2 over 9 equals...
Click here to see answer by Alan3354(69443)

Question 942661: 7 2
- - - =
9 9

7 over 9 minus 2 over 9 equals...
Click here to see answer by josgarithmetic(39618)

Question 942661: 7 2
- - - =
9 9

7 over 9 minus 2 over 9 equals...
Click here to see answer by MathTherapy(10552)

Question 942641: g(x)= (5-x^3)^7
g'(x)=
Click here to see answer by Alan3354(69443)

Question 942732: Hello! Here is the question I need help understanding:
"Write an equation for a linear function whose graph has the given characteristics: (-2,2)(2,-12)
I have tried m=y2-y1 over x2-x1, and I get -14/4 but that answer comes back incorrect. Please tell me what I'm doing wrong. Thank you so much
Click here to see answer by josgarithmetic(39618)

Question 942845: what is a domain of f(x)=5-2x
Click here to see answer by MathLover1(20850)

Question 942923: Express the area A of a 30-60-90 degree triangle as a function of the length h, where h is the shortest side.
Click here to see answer by josmiceli(19441)

Question 942978: Give an example of an increasing function whose domain is the interval [0, 1] but whose range does not
equal the interval [f (0), f (1)].
Click here to see answer by richard1234(7193)

Question 943204: Lisa earns $7.50 per hour mowing lawns.
a. Write a rule to describe how the amount of money m earned is a function of the number of hours h spent mowing lawns.
b. How much money does Lisa earn if she works for 5 hours and 45 minutes?
Multiple Choice Answers
1. m(h)=5h+45; $37.95
2. m(h)= (h/7.50); $1.30
3. m(h)=7.50h; $40.88
4. m(h)=7.50h; $43.13
Click here to see answer by macston(5194)

Question 943215: Tell whether the sequence is arithmetic. If it is, what is the common difference?
1, 1 1/4, 1 1/2, 1 3/4
1. yes; 4
2. yes; 1/4
3. yes; 1/2
4. no
Click here to see answer by rfer(16322)

Question 942930: Given that f(x) is one-to-one, if f(2)=6 and f(3)=7, find:
a.)f^-1(6)
b.)f^-1(f(3))
thank you for your time
Click here to see answer by Fombitz(32388)

Question 943410: How do i write this: h is the function that takes the reciprocal of the input and then takes the absolute value of the result
Click here to see answer by stanbon(75887)

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