1. 1.
Evaluating Expressions and Functions
Example 1: Evaluate the following expressions when a = -2, b = -5, c = 7
2ab – 3ac + 2abc
2(-2)(-5) – 3(-2)(-5) + 2(-2)(-5)(7)
3a2 – 2b3c
3(-2)^2 – 2(-5)^3(7)
│a – b – c + abc │
Abs( -2 – (-5) – 7 + (-2)(-5)(7))

2. 1.
Evaluating Expressions and Functions
Function Notation
f(x) means output when input is x for a given rule f(x)
f(x) = h(x) = h(a) = g(x) = h(b) = y = OUTPUT
Example 2: Evaluate f(x) when x = 7
f(x) = 2x – 10
f(7) = 2(7) – 10
f(7) = 4

3. 1. Example 3: Evaluate f(-3), for the following functions, f(x), if:
Evaluating Expressions and Functions
Example 3: Evaluate f(-3), for the following functions, f(x), if:
a. f(x) = 2x3 – 2x + 10
f(-3) = 2(-3)3 – 2(-3) + 10 = -38
b. f(x) = 3x(5 – 2x2)(4 + 3x)
f(-3) = 3(-3)[5 – 2(-3)2][4 + 3(-3)]
f(-3) = -9(-13)(-5) = -585
c. f(x) = │(x – 5)3│
f(-3) =│((-3) – 5)3│= 512

4. 1. Example 3: Evaluate the following functions
Evaluating Expressions and Functions
Example 3: Evaluate the following functions
a. g(a) = 10a2 – 5; g(-5)
g(-5) = 10(-5)2 – 5 = 245
b. h(b) = -3b + 15; h(-2.5)
h(-2.5) = -3(-2.5) + 15 = 22.5
c. z(x) = │z – 5│- 25; z(5)
z(5) = │5 – 5│- 25 = -25

5. 1. Example 4: Evaluate the following functions a. g(a) = a + 5; g(2a)
Evaluating Expressions and Functions
Example 4: Evaluate the following functions
a. g(a) = a + 5; g(2a)
g(2a) = (2a) + 5 = 2a + 5
b. h(t) = -3t + 15; h(5t)
h(5t) = -3(5t) + 15
h(5t) = -15t + 15
c. z(x) = 2x – 5; z(x – 4)
z(x-4) = 2(x – 4) – 5

6. 1. Example 5: Evaluate the following functions
Evaluating Expressions and Functions
Example 5: Evaluate the following functions
a. g(a) = a2 + 5; g(-3a)
g(-3a) = (-3a)2 + 5 = 9a2 + 5
b. h(t) = 3t3 + 15; h(t2)
h(t2) = 3(t2) = 3t6 + 15
c. z(x) = 2x4 – 5x2; z(4x)
z(4x) = 2(4x)4 – 5(4x)2 = 512x4 – 80x2