How do I know when to shower the power?

Question

In this problem, f(x) = 2x+1 & g(x) = 3x^2,
which represents g(f(x)) ?

The answer is 12x^2 + 3 ...
so that means within solving it, I showered the power.

BUT when it came to a problem like this,:
x+2 = square root of x + 8,
[once you're in the middle of the steps,
it seems like you could shower the power,
but in reality you use foil to get the answer] ..

So yeah. I know you can't shower the power
when the sign is negative, so therefore,
you do it when it's positive. How should I know
when to use FOIL or just shower the power ?

It's when you do something like this -

(3x^2)^2
Then you shower the exponent into the equation to get the answer, which will then be 9x^4...

Philo, for the first problem that's what I got, but it wasn't part of the answer choices therefore I had to 'shower the power.'

Haha. My teacher taught it to me.Now I realize it isn't universal language.

Answer 1

if f(x) = 2x + 1 and g(x) = 3x², then
g(f(x)) 3(2x+1)² = 3(4x² + 4x + 1) = 12x² + 12x + 3, so what you call the answer is wrong.

I can only guess that when you say "shower the power" you mean that (xy)² = x²y², that the exponent is applied to each factor in the multiplication. FOIL is used when a sum or difference is raised to a power.

Who on earth taught you such silly vocabulary? FOIL is almost universal, but in 35 years teaching I've never heard of the other.

Answer 2

showering the power??? what is that?

Answer 3

I can't understand your question,can you please explain slowly.