-1/4x²y²+0.09;4x²-(x-y)²;-(a+b)²+(2b-3b)²;
问题描述:
-1/4x²y²+0.09;4x²-(x-y)²;-(a+b)²+(2b-3b)²;
1000²/252²-248²;(1-1/2²)(1-1/3²)(1-1/4²)…(1-1/100²);49(x-2)²-25(x-3)²;1.22²×9-1.33²×4;
答
-1/4x²y²+0.09;=(0.3)²-(xy/2)²=(0.3+xy/2)(0.3-xy/2) 4x²-(x-y)²;=(2x+x-y)(2x-x+y)=(3x-y)(x+y) -(a+b)²+(2b-3b)²=(2a-3b)²-(a+b)²=(2a-3b+a+b)(2a-3...