### Home > INT3 > Chapter 1 > Lesson 1.1.3 > Problem 1-45

1-45.

** **If 1 is the output for Carmichael’s function machine shown at right, how can you determine what number is dropped in? Calculate the number(s) that could have been dropped in. Homework Help ✎

Since 1 is the output, set the expression inside of the function machine equal to 1.

*x*^{2} + 2*x* + 1 = 1

*x*^{2} + 2*x* = 0

*x*(*x* + 2) = 0

Use the Zero Product Property: *x* = 0, *x* = −2