Question

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EVALUATING FUNCTIONS
The symbol f(x) represents the real number in the range of the function
f corresponding to the domain value x. Symbolically, f:x→f(x). The ordered
pair (x, S(x)) belongs to the function f. Ifxisa real number that is not in the
domain of f, then fis not defined at x and f(x) does not exist.
Examples:
15
a)
Find f(6), S(a), and f(6+a) for f(x)
三
3°
X -
b)
Find g(7), g(h), and g(7+h) for g(x)
= 16+ 3x
x.
2
Find k(9), 4k(a), and k(4a) for k(x)
Vx
c)
2
For the above functions, determine the resulting domain.
Solutions:
a)
b)
c)

Answers (page 5)
15
「(x)=
Rational function
a
f(6) = 15 /6 -3= 15 /3 = 5
f(a) = 15 / a - 3
f(6+a) = 15 / 6+a-3=15/a+3
Restriction: The denominator cannot be equals to 0
x-3+0
X+3
Domain: {xe RIx + 3}
bg(x)=16+3x-x° Quadratic function
g(7)=16+3(7) -7° =-12
g(h)
= 16+3h-h°
g(7+h)=16+3(7+h)-(7+h)°
(49+14h+*)
=16+21+3h-
= 37+ 3h-49-14h-h°
=-° -11h-12
(7+h)(7+h) =49+7h+7h+h°
= 49+14h+
Domain: {x e R}