A function evaluation gives you an input in parentheses and asks for the output. Replace every with that input, including the in the denominator. In Desmos, define the function, then evaluate it on the next line. Keep subtraction in its original order: reversing the denominator changes the sign of the result.
Hints
- Hint 1
The number inside is the input. It takes the place of every , including the one below the fraction bar. What does the denominator, , become?
- Hint 2
A denominator is the bottom of a fraction. Keep the original order when you enter the rule in Desmos, then ask Desmos for the output at input .
Step-by-step
Define and evaluate in Desmos
Step 1Save the function rule
means put in for every , in both the top and bottom of the fraction. Type in Desmos. This defines the function, the rule you'll use to find the output.
- Step 2
Read the output
Type on the next line. Desmos puts into the saved rule and prints . The denominator, or bottom, becomes , not ; reversing it would flip the sign. The output is . Choice D.