12.2的平方*9-1.33的平方*4

题目

12.2的平方*9-1.33的平方*4
利用分解因式算

答案

12.2的平方*9-1.33的平方*4
=12.2^2*3^2-1.33^2*2^2
=(3*12.2+1.33*2)(3*12.2-1.33*2)
=(36.6+2.66)(36.6-2.66)
=39.26*33.94
=1332.4844
12.2的平方*9-13.3的平方*4
=12.2^2*3^2-13.3^2*2^2
=(3*12.2+13.3*2)(3*12.2-13.3*2)
=(36.6+26.6)(36.6-26.6)
=63.2*10
=632
1.22的平方*9-1.33的平方*4
=1.22^2*3^2-1.33^2*2^2
=(3*1.22+13.3*2)(3*1.22-1.33*2)
=(3.66+2.66)(3.66-2.66)
=6.32*1
=6.32