Question

I don't understand this function notation, can you please help?

If f(x) = x 2 + 1 and g(x) = 3x + 1, find f(-1) + 5g(-3).


-40
-38
7

Answer 1

are these your functions:
\(\large f(x)=x^2+1 \) and \(\large g(x)=3x+1 \) ???

Answer 2

Yes.

Answer 3

find f(-1), which x=-1, and do the same for g(x)

Answer 4

f(-1) means to evaluate the expression when x=-1.. so \(\large f(-1)=(-1)^2+1 \)

Answer 5

can you do that with g((-3)...????

Answer 6

okay.. Let me try that...

Answer 7

So, If I'm doing this right...

-1 + 15 (-3) is what I solve, right?

Answer 8

is that for g(-3)???

Answer 9

Yes.

Answer 10

\(\large g(-3)=3(-3)+1 = \) ????
can you evaluate g(-3) now?

Answer 11

so g(-3) would be -8

Answer 12

ok.. good...

Answer 13

and what was f(-1) = ????

Answer 14

Dont forget the 5 in front of 5g(-3) =0

Answer 15

I think that my problem is trying to get to that final step.. I can't figure out what's wrong with my work... oh and f(-1) = 1

Answer 16

i don't think that's right... try again... f(-1) = ???

Answer 17

well if it's (-1) squared + 1... -1 squared is 1 + positive one... oh wait.. 0??

Answer 18

\(\large f(-1)=(-1)^2+1=(-1)(-1)+1=2 \)

Answer 19

f(x) = x 2 + 1 and g(x) = 3x + 1, find f(-1) + 5g(-3).
f(-1)=(-1)^2+1
f(-1)=1+1
f(-1)=2

5g(-3)=5*((3*(-3))+1)
5g(-3)=5*(-8)
5g(-3)=-40
f(-1)+5g(-3)=2+(-40)=-38

Answer 20

I'm following..

Answer 21

looks like he ^^^ did the rest for u....