Question

因式分解题 (a^2-b^2)^2+(a^2-b^2)-18

Answer 1

(a^2-b^2)^2+(a^2-b^2)-18

=(a²-b²)²+(a²-b²)+1/4-1/4-18

=(a²-b²+1/2)²-73/4

=(a²-b²+1/2-1/2√73)(a²-b²+1/2+1/2√73)