一道数学计算题...请写出计算过程...[(2a-1/3b)²+(2a+1/3b)²](2/9b²-8a²)
问题描述:
一道数学计算题...请写出计算过程...
[(2a-1/3b)²+(2a+1/3b)²](2/9b²-8a²)
答
展开就行了,解:[(2a-1/3b)²+(2a+1/3b)²](2/9b²-8a²)=(8a^2+2/9b^2)*(2/9b^2-8a^2)
=4/81b^4-64a^4
答
[(2a-1/3b)²+(2a+1/3b)²](2/9b²-8a²)
=(4a^2-(4/3)ab+1/9b^2+4a^2+(4/3)ab+1/9b^2)(2/9b²-8a²)
=(2/9b²+8a²)(2/9b²-8a²)
=4/81b^4-64a^4