Answer:
Step-by-step explanation:
M²N² - MN = MN (MN - 1)
M²N² + MN = MN (MN + 1)
[tex]\frac{(M^{2}N^{2}-MN)(M^{2}N^{2}-MN)}{MN}= \frac{MN(MN-1) * MN(MN + 1)}{MN}\\[/tex]
= (MN - 1) * MN * (MN + 1)
= (MN - 1)(MN +1) MN {(a+ b)(a - b) = a² - b² }
= (M²N² - 1²) * MN
= (M²N² - 1)MN
