Question 16·Easy·Nonlinear Functions
The function is defined by . What is the value of ?
(Express the answer as an integer)
For function-evaluation questions, immediately substitute the given input into the function rule, then use strict order of operations: handle exponents (including negative signs inside parentheses) before multiplication and addition. Write each intermediate step—especially with negatives—to avoid sign mistakes, and keep the work short and vertical so you can quickly verify each operation under time pressure.
Hints
Use the function rule
The function tells you how to turn any input into an output: . To find , plug in for everywhere.
Follow the order of operations
After substituting for , make sure you square before multiplying by 4, then add 3 at the end.
Be careful with the negative sign
When you square , the result is positive because is positive. Make sure you don’t keep the negative sign after squaring.
Desmos Guide
Enter the expression for g(-2)
In Desmos, type 4(-2)^2 + 3 exactly as shown. Desmos will automatically follow the correct order of operations.
Read the output
Look at the numerical value that Desmos displays for 4(-2)^2 + 3; that is the value of .
Step-by-step Explanation
Substitute the input into the function
The function is defined as . To find , replace with :
Evaluate the exponent first
By order of operations (PEMDAS), handle the exponent before multiplying:
- Square : .
So the expression becomes:
Multiply, then add to get the final value
Now multiply and then add:
So the value of is 19.