4(A+2B)²-25(a-b)²因式分解.谁帮做下.
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/01 15:24:07
![4(A+2B)²-25(a-b)²因式分解.谁帮做下.](/uploads/image/z/2983370-50-0.jpg?t=4%28A%2B2B%29%26%23178%3B-25%EF%BC%88a-b%EF%BC%89%26%23178%3B%E5%9B%A0%E5%BC%8F%E5%88%86%E8%A7%A3.%E8%B0%81%E5%B8%AE%E5%81%9A%E4%B8%8B.)
xJ@_eA
6(9l@^,EAc
H2g8pXC~I-wUF^)탗2/V;I
#[I=^\.U{1M&Yϭv#3VyBl UNN}#l?{
4(A+2B)²-25(a-b)²因式分解.谁帮做下.
4(A+2B)²-25(a-b)²因式分解.谁帮做下.
4(A+2B)²-25(a-b)²因式分解.谁帮做下.
(一)
4(A+2B)²-25(a-b)²
= {2(A+2B)}² - {5(a-b)}²
= {2(A+2B) + 5(a-b)} {2(A+2B) - 5(a-b)}
= (2A+4B + 5a-5b) (2A+4B- 5a+5b)
(二)
4(a+2b)²-25(a-b)²
= {2(a+2b)}² - {5(a-b)}²
= {2(a+2b) + 5(a-b)} {2(a+2b) - 5(a-b)}
= (2a+4b + 5a-5b) (2a+4b- 5a+5b)
= (7a-b) (-3a+9b)
= - 3 (7a-b) (a-3b)
设x=A+2B y=a-b
则原式=4x²-25y²
=(2x)²-(5y)²
=(2x+5y)(2x-5y)
将x、y代入
则原式=[2(A+2B)+5(a-b)][ 2(A+2B)-5(a-b )]
=(2A+4B+5a-5b)(2A+4B-5a+5b)
[2(A+2B)+5(a-b)][2(A+2B)-5(a-b)]