If F( t ) = 8- 9t - 4t ^ { 2} , what is F(-1)?

1 Answer
Nov 2, 2017

F(-1)=13

Explanation:

A function is a set of rules that takes some value and maps or associates it with another. Here, the "rules" of our function F take some input value t and map it to a new value, F(t) (read "F of t" or "the value of F at t"), according to the rule 8-9t-4t^2. To find where a particular value t will be mapped to under those rules, we just need to run it through the expression.

In this case, where t=-1, the value F will map t to will be 8-9(-1)-4(-1)^2. Simplifying that expression, we get:

F(t)=8+9-4=17-4=13