问题补充:
1.(x+3)二次方-(x-1)(x-2) 2.(x二次方y)三次方乘以(-2y二次方)二次方除以(2x二次方)(a+b)(a-b)+(a+b)二次方-2a二次方,其中a=3,b=—三分之一
答案:
(x+3)^2-(x-1)(x-2)
=x^2+6x+9-(x^2-3x+2)
=x^2+6x+9-x^2+3x-2
=9x+7(x^2y)^3*(-2y^2)^2÷(2x^2)
=(x^6y^3)*(4y^4)÷(2x^2)
=(4x^6y^7)÷(2x^2)
=2x^4y^7
======以下答案可供参考======
供参考答案1:
(x+3)^2-(x-1)(x-2)
=x^2+6x+9-(x^2-3x+2)
=x^2+6x+9-x^2+3x-2
=9x+7(x^2y)^3*(-2y^2)^2÷(2x^2)
=(x^6y^3)*(4y^4)÷(2x^2)
=(4x^6y^7)÷(2x^2)
=2x^4y^7