计算 ①(x+1)²+2(1-x)②(a-2b)(a+2b)-(a+2b)²+8b²
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 18:34:46
![计算 ①(x+1)²+2(1-x)②(a-2b)(a+2b)-(a+2b)²+8b²](/uploads/image/z/629349-69-9.jpg?t=%E8%AE%A1%E7%AE%97+%E2%91%A0%EF%BC%88x%2B1%EF%BC%89%26%23178%3B%2B2%EF%BC%881-x%EF%BC%89%E2%91%A1%28a-2b%29%28a%2B2b%29-%28a%2B2b%29%26%23178%3B%2B8b%26%23178%3B)
计算 ①(x+1)²+2(1-x)②(a-2b)(a+2b)-(a+2b)²+8b²
计算 ①(x+1)²+2(1-x)
②(a-2b)(a+2b)-(a+2b)²+8b²
计算 ①(x+1)²+2(1-x)②(a-2b)(a+2b)-(a+2b)²+8b²
x^2+2x+1+2-2x=x^2+3
=a^2-4b^2-a^2-4ab-4b^2+8b^2=-4ab
①(x+1)²+2(1-x)
=x²+2x+1+2-2x
=x²+3
②(a-2b)(a+2b)-(a+2b)²+8b²
=a²-4b²-a²-4ab-4b²+8b²
=-4ab