13(1) (at2ab+b2)(a²-zab+62)
(a362)をMをおく
(与式)=(M+zab)(M-2ab)
=M² 4a²²
= (a²+ b²)² - 4a²b²
= a²+2a²b² = 64-4a²b²
-at-ea² 6² + 64
(2)(x1)(21)=x4-1
(3)(23)をMeおく
(与式)=(M+2%)(M-2x)
= M²-4x²²
=(x+3)=4x
=x46x+4-4
=x4+2x+9
(4)(y-Z)をMをおく
(与式)=(x-1)(x+M)
=9c2-M2
= x² (1-2)²
= x² (y² = 212 + 2 ²)
-
= x² 4²² + 2 4 2-22