x²-(x+2)(x-2)-(x+3)².求大师们速速回答!要有正确的解题方法!
问题描述:
x²-(x+2)(x-2)-(x+3)².求大师们速速回答!要有正确的解题方法!
答
x²-(x+2)(x-2)-(x+3)²
=x²-(x²-4)-(x²+6x+9)
=x²-x²+4-x²-6x-9
=-x²-6x-5