(1)(2x-5y)^2 (2) (-1/3x+3/2y)^2 (3) (-2x-5y)^2 (4)(1/2x-4y)^2
问题描述:
(1)(2x-5y)^2 (2) (-1/3x+3/2y)^2 (3) (-2x-5y)^2 (4)(1/2x-4y)^2
初一题啊!
答
(2x-5y)^2
=4x²-20xy+25y²
(-1/3x+3/2y)^2
=1/9x²-xy+9/4y²
(-2x-5y)^2
=4x²+20xy+25y²
(1/2x-4y)^2
=1/4x²-4xy+16y²