Question

use the function to answer the question:
x+14 if x<-7
f(x) 21 if -7 ≤x<-6
x^2 -1 if x ≥ -6
what is the value of f(-6)?

Answer 1

Since u want to find F(x) at x=-6 ,
U will use the Function F(x)= x^2-1 because x is bigger or **Equal** -6
Plug -6 in the equation so it will be
F(-6)=(-6)^2-1=.....

Answer 2

35?

Answer 3

yup,35

Answer 4

Bingo!

Answer 5

what about
f(x)=x^2-4; g(x)=x+2
which is equal to (f+g)(x)

Answer 6

U mean Find F(F(x)+g(x)) ?

Answer 7

no its f(x)+g(x)
im not to sure but i think that might be it

Answer 8

then just add them
x^2-4+x+2 = ?

Answer 9

x^2+x-2?

Answer 10

yup

Answer 11

okay so what is f(x)=4x-1
g(x)=5x^2
which is equal to (fºg)(x)?

Answer 12

for (fog)(x) , replace 'x' in f(x) by g(x) = 5x^2

Answer 13

so then :
4(5x^2)-1

Answer 14

yup, that will be 20x^2-1

Answer 15

and then what is
f(x)=4x-7
g(x)=x+3
what is the function of (gºf)(4)

Answer 16

is it 12?

Answer 17

to get (gof)(x)
replace 'x' in g(x) by f(x) and then put x=4

Answer 18

yup, its 12

Answer 19

what is f(x)=5x-10
what is the value of f^-1 (-3)

Answer 20

http://openstudy.com/study#/updates/50615c4ce4b02e139411444b

Answer 21

so got that, its 1.4

Answer 22

yea

Answer 23

any more questions to come ?

Answer 24

yea

Answer 25

what is the vertex of the graph of f(x)=-2|x-5|+3

Answer 26

i think its -5, 3

Answer 27

+5,3

Answer 28

nopes, (5,3)
vertex for f(x) = p|x+a|+b
is -a,b

Answer 29

ohhh okay

Answer 30

the graph of g(x) results when the graph of f(x)=-|x| is shifted 3 units to the left.
i think it's g(x)=-|x+3|

Answer 31

what is the value of f(-4)
when f(x)=
-10 if x< -5
x^3 if -5≤x≤2
2x+4 if x>2

Answer 32

in which range does -4 lie ?

Answer 33

the middle one and the last one

Answer 34

not the last one, x>2 means x cannot be -4
so only middle one.
put x= -4 in middle function, what do u get ?

Answer 35

-64

Answer 36

thats your answer :)

Answer 37

okay now this one is kinda confusing to me but i think i know the answer....

Answer 38

i think it is the third one, but im not too sure....

Answer 39

nopes, its 4th.
put these values, x=0,0.5,1,1.5,..., find g(x)
u will get it

Answer 40

ohhhh i get it!!! its soo confusing sometimes!

Answer 41

f(x)=2x+5
g(x)=3x^2

which is equal to (fºg)(x)?

i tried it and i got 3x^2+2x+5 but i think it's wrong....

Answer 42

put x= 3x^2 in f(x)
2(3x^2)+5 = ?

Answer 43

6x^2+5?

Answer 44

yup.

Answer 45

omg you make it easier to understand hahaha

Answer 46

more questions ? i need to go...

Answer 47

yea one last one
f(x)=2/x
g(x)=|x|-1
what is the domain of (fºg)(x)

Answer 48

fog (x) = ?

Answer 49

x|x=real numbers
x|x ≠0
x|x≠0, x≠1
x|x≠-1, x≠1

Answer 50

f(g(x)) = 2/(|x|-1)
ok?
for which values is denominator = 0 ??

Answer 51

no the ones i put up last were the options

Answer 52

i know.
denominator should not be 0
|x|-1 should not be 0
for x=1, |1|-1=1-1=0
for x=-1, |-1|-1=1-1=0
so x|x≠-1, x≠1
got it ?

Answer 53

ohh okay yea! thank you! you make it easier to understand ty very much

Answer 54

welcome :)