In function evaluation, you're given a rule and an input and asked for its output. The number inside the parentheses replaces the variable in the rule. Enter the function in Desmos, then type its name with the given input in parentheses. Keep every operation in the rule, especially a subtraction after multiplication.
Hints
- Hint 1
A function is a rule that turns an input into an output. In , the input is the number inside the parentheses. What replaces in the rule?
- Hint 2
An output is what the function returns after applying its entire rule. Here, you multiply the input by and then subtract . What would you miss if you stopped after multiplying?
Step-by-step
Substitute the input and evaluate
Step 1Put the input into the rule
In , is the input, so it replaces : . The stays outside the multiplication. Type into Desmos to store the rule for the next line.
- Step 2
Read the output
Type on the next line. Desmos shows , the output when the input is . So the value of is . Choice D.