Helppp
so the function notation f(a) means "the value of the function f when a is substituted into the equation for x"
so f(2) means "the value of the function f when 2 is substituted into the equation for x"
so to find f(2) replace "x" with 2 and find f(x) = 3x^2 + 2x + 4
20
good! now we replace "x" with "a+h" and find f(x) = 3x^2 + 2x + 4 your answer will not be a number, it will be a polynomial with a and h
wait I got.. \[3a^2+3h^2+2a+2h+4\]
be careful (a+h)^2 is not a^2 + h^2 (this is a really common mistake though)
(a+h)^2 = (a+h)(a+h) = ? use foil to expand this
what am I solving for again a or h?
you are not solving for a or h
f(a+h) just means, find f(x) when x = a + h therefore we are just plugging in "a+h" into f(x) and simplifying
3x^2 + 2x + 4 = 3(a+h)^2 + 2(a+h) + 4 = ?
\[3a^2+6ah+3h^2+2a+2h+4\]
awesome, that's the answer
Great !!! Now for #12
f○g = f(g(x)) to find f○g(2) we simply find g(2), take the result of that, and find f(x) of that value
so g(2) = ?
17
good and f(17) = ?
sorry I was afk
\[\frac{ 1 }{ 17 }\]
good so that's the ans to f○g(2)
to find (f+g)(2) just add f(x) and g(x) together then let x = 2
17.5
good that's it for 12
for 13 we use a similar process to 12 but we use the table instead of an equation
g(1) = ?
6
good and f(6) = ?
17
good that's it for 13
so just 6 and 17
the answer is 17 not 6
oh because g(1) is 6
yes
so the final answer is 17
yes
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