Amino acids are used to build ?

Polypeptides

Step-by-step explanation:

A sequence of amino acids are joined together by peptide bonds to form a polypeptode chain;

This chain then folds and twists (via intramolecular forces/attractions) into a 2D or 3D shape and may even join with another polypeptide chain to form a protein.

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option