Hi butterflies. This exercise is about forming new functions from other functions. You've learned how to combine like-terms, yes? For example, you know that 4x^2 and 3x^2 are like-terms; if we add them, we get 7x^2.
The expression f(x) + g(x) tells us to add the two given functions f and g:
x^2 + 9 + x^2 + 4
Now simplify that result, by combining all the like-terms.
In the same way, the expression f(x)-g(x) means g(x) is subtracted from f(x). Therefore, subtract the terms in function g (x^2 and 4) from the terms in function f. Simplify the result, by combining like-terms.
We also form new functions by multiplying or dividing other functions.
The expression f(x) g(x) means the product f(x) times f(g). Do you know how to multiply two binomial expressions? Perhaps, you've seen the FOIL description of the steps (basically, use the distributive property twice):
(a + b)(c + d) = a*c + a*d + b*c + b*d
Try that pattern, replacing symbols a and c with x^2, and letting b=9 and d=4.
f(x)/g(x) tells us to divide function f by function g. That forms a new (rational) function, with f(x) in the numerator and g(x) in the denominator.
Let us know, if you need more help. Please show any attempts thus far, so we can see what you've tried. Otherwise, please explain which parts you don't understand.
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