Given the following functions f(x) and g(x), solve for (f ⋅ g)(2) and select the correct answer below:

f(x) = 3x2 + 2

g(x) = x − 8

−42
−84
42
84

Question

Given the following functions f(x) and g(x), solve for (f ⋅ g)(2) and select the correct answer below:

f(x) = 3x2 + 2

g(x) = x − 8

 −42
 −84
 42
 84

anonymous · Answer

@iGreen

misty1212 · Answer

HI!!

anonymous · Answer

hi :D

misty1212 · Answer

$$f(x)=3x^2+2$$ right?

anonymous · Answer

Yeah

misty1212 · Answer

ok then '
$$f(2)=3\times 2^2+2$$ what is that number?

anonymous · Answer

I got 68

misty1212 · Answer

think you did the "order 'o operations" wrong
square first, then multiply

anonymous · Answer

How do I square?

igreen · Answer

$\sf 2^2 \rightarrow 2 \times 2$

misty1212 · Answer

how do you square a number?  multiply it by itself
so $$2^2=2\times 2$$

anonymous · Answer

so it'd be f(2)=3×2x2+2?

misty1212 · Answer

yes what is 
$$
3\times 2\times 2+2$$?

anonymous · Answer

14

misty1212 · Answer

right
now hold on to that number

anonymous · Answer

Alright

misty1212 · Answer

$$g(x)=x-8$$ what is 
$$g(2)$$?

anonymous · Answer

g(2) = x - 8?

misty1212 · Answer

hmmm i see you are a bit confused as to how to evaluate a function

anonymous · Answer

Very :/

misty1212 · Answer

$$g(x)=x-8\
g(\spadesuit)=\spadesuit-8\
g(\xi)=\xi -8$$

misty1212 · Answer

so how do you find $g(2)$? 
where you see an $x$ replace it by a $2$

anonymous · Answer

g(2) = 2 - 8? The other two functions have clovers and & signs in them, not sure if it's meant to be there.

misty1212 · Answer

yeah$$g(2)=2-8$$

anonymous · Answer

So what's the next step?

misty1212 · Answer

find $$2-8$$

anonymous · Answer

-6, if i'm solving from left to right

anonymous · Answer

g(2) = -6?

misty1212 · Answer

yes it is $-6$ no matter what you do

misty1212 · Answer

final step 
$$f\times g(2)=f(2)\times g(2)=14\times (-6)$$

anonymous · Answer

so the final answer woulds be -84?

misty1212 · Answer

yes

anonymous · Answer

Thanks :))
Could you help me with a few more?

misty1212 · Answer

lol sure we can at least do one more

anonymous · Answer

Sweet :)

anonymous · Answer

Gaming systems are on sale for 20% off the original price (g), which can be expressed with the function p(g) = 0.8g. Local taxes are an additional 12% of the discounted price (p), which can be expressed with the function c(p) = 1.12p. Using this information, which of the following represents the final price of a gaming system with the discount and taxes applied?

 c(p) + p(g) = 1.92g
 c[p(g)] = 0.896g
 g[c(p)] = 1.92p
 c(p) ⋅ p(g) = 0.896pg

anonymous · Answer

This seems like an easy one, it's just the trouble of setting up the function I guess

misty1212 · Answer

it is easy 
it is the last one

anonymous · Answer

How did you get that?

misty1212 · Answer

lets do it with an item that cost $100

misty1212 · Answer

first take the 20% discount, multiply 
$$100\times .8=80$$

misty1212 · Answer

so it is $80 before the tax
then put in the tax  get 
$$80\times 1.12=89.6$$

misty1212 · Answer

what did we do? first multiply by $.8$ then multiply by $1.12$

misty1212 · Answer

ohh hold the phone for a second

misty1212 · Answer

i see what they want you to say, they want you to pick B

anonymous · Answer

Oooh so it's B?

misty1212 · Answer

first do $p$ then do $c$ it is $$c(p(g))$$

misty1212 · Answer

which is kind of silly since you can do it just by multiplying, but whatever 
pick B

anonymous · Answer

Alright that's what I was thinking too haha, thank you. Couple more :D?

anonymous · Answer

Or would you rather me open a new question to give you another best response?