Question

Okay I still don't really understand how to do this..

Answer 1

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

Answer 2

\(\Huge 2 \times f [g (x)]\)

Answer 3

what I got is 2(2x^2 + 5)(-3x)

Answer 4

\(\Huge 2 \times f[value-of-g(-1)]\)

Answer 5

f(x)= ........
f(-1)= substitute -1 into x
fg(x)= f[g(x)]= substitute value of g(x)

Answer 6

I don't understand what you just did :/

Answer 7

example:
f(x)=2x
g(x)=3x
fg(2)=f[g(2)]= f[ 3x2]=6x2=12

Answer 8

still don't understand that I'm sorry

Answer 9

Okay I'm going to try to do the problem then maybe you could check me

Answer 10

ok f(x)= 2x
how do u find the value of f(1)

Answer 11

P/s: rmb the bracket in function isnt meant for multiply

Answer 12

2(2x^2 + 5)(-3x)
2(-6x^3 - 15x)
-12x^3 - 30x
-12(-1)^3 - 30(-1)
12 + 30 = 42

Answer 13

Wrong.

Answer 14

That's what someone else got when they did it :/

Answer 15

1st step should be 2[2(-3x)^2+5]

Answer 16

when f(x)= 2x
you substitute x=1 to find f(1)=2
--------------------------------
so when fg(x) its = f[g(x)]
where g(x) is a value after u substitute -1 into the function
and then u take the value after u solve for g(x) substitute into the function f(x)

Answer 17

Let g(x)=y
fg(x)= f[g(x)]= f(y)

Answer 18

I don't understand when you make it all f(g)(f) terms and stuff, it goes right over my head :/

Answer 19

fg(x) = f[ g(x) ] remember this
then assume g(x) is a number A NUMBER!
so after u find the number that represent g(x)
go substitute into f(x)

Answer 20

if u stl not understand, bump this question. i tried my best to guide you but failed.

Answer 21

Okay, thank you anyway!