Video Transcript
If 𝑓 of 𝑥 is equal to
negative eight 𝑥 squared minus three 𝑥 plus four, find 𝑓 of negative
three.
We’re asked to find the value
of 𝑓 of negative three. And we recall that this is
function notation for the value of 𝑓 of 𝑥 when 𝑥 is equal to negative
three. This means in our function 𝑓
of 𝑥, wherever we have an 𝑥, we substitute negative three. So, we have 𝑓 of negative
three is equal to negative eight times negative three squared minus three times
negative three plus four. That is negative eight times
nine plus nine plus four, which evaluates to negative 59. Hence, 𝑓 of negative three is
equal to negative 59.
