作业帮 > 数学 > 作业

计算:21×101²-99²×21=------- 因式分解:1.(x-y)(x+y)-(x+y)&

来源:学生作业帮 编辑:搜搜考试网作业帮 分类:数学作业 时间:2024/08/18 21:40:40
计算:21×101²-99²×21=------- 因式分解:1.(x-y)(x+y)-(x+y)² 2.(-2a-1)(3a-2)
计算:21×101²-99²×21=------- 因式分解:1.(x-y)(x+y)-(x+y)² 2.(-2a-1)(3a-2)+(-2a+3)² 计算:1.20021021²-20021020×20021022 2.(2+1)(2²+1)(2四次方+1)(2八次方+1)+1
计算:21×101²-99²×21=------- 因式分解:1.(x-y)(x+y)-(x+y)&
21×101²-99²×21=21×(101²-99²)=21×(101+99)×(101-99)=8400
(x-y)(x+y)-(x+y)²=(x+y)(x-y-x-y)=-2y(x+y)
(-2a-1)(3a-2)+(-2a+3)² =-2a²-11a+11 =-(4a-11+根号209)(4a-11-根号209)/8
20021021²-20021020×20021022=20021021²-(20021021-1)×(20021021+1)
=20021021²-20021021²+1=1
(2+1)(2²+1)(2^4+1)(2^8+1)+1=(2-1)(2+1)(2²+1)(2^4+1)(2^8+1)+1
=(2²-1)(2²+1)(2^4+1)(2^8+1)+1=(2^4-1)(2^4+1)(2^8+1)+1=(2^8-1)(2^8+1)+1=2^16