Evaluating Function Expressions

The video tutorial explains how to evaluate function expressions by substituting values into functions and simplifying the resulting expressions. It covers multiple examples, including evaluating f(1), g(4), f(-3), g(-7), f(1), g(9), f(7), and g(-1). The tutorial emphasizes the importance of using parentheses to avoid sign errors during multiplication and subtraction. Each example demonstrates the process of finding the y-value for a given x-value on a graph and then performing arithmetic operations to simplify the expression.

What is the main focus of this video tutorial?

• Solving quadratic equations

• Evaluating different function expressions

• Simplifying algebraic expressions

• Evaluating functions from graphs

What is the y-value of f when x=1?

• 2

• 1

• 0

• -2

What is the y-value of g when x=4?

• 0

• 6

• 4

• -4

What is the result of the expression -8 * f(1) - 4 * g(4)?

• 8

• -8

• 16

• -16

Why is it important to use parentheses when substituting negative numbers?

• To avoid mistakes with signs

• To make the expression look neat

• To ensure correct order of operations

• To simplify the expression

What is the y-value of f when x=-3?

• -3

• 3

• 0

• -1

What is the y-value of g when x=-7?

• -6

• 6

• 0

• -7

What is the result of the expression -6 * f(-3) - 5 * g(-7)?

• -12

• 12

• 18

• -18

What is the y-value of f when x=1 in the second evaluation?

• -1

• 0

• 5

• -5

What is the y-value of g when x=9?

• -6

• -9

• 0

• 6