a²(x-y)+b²(y-x) ; 2-½x² ;(a+2b)²-4(a-b)²; 9(a+b)²-4(a-b)²²(平方) ½(二分之一)
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/02 02:23:56
![a²(x-y)+b²(y-x) ; 2-½x² ;(a+2b)²-4(a-b)²; 9(a+b)²-4(a-b)²²(平方) ½(二分之一)](/uploads/image/z/14890282-34-2.jpg?t=a%26%23178%3B%EF%BC%88x-y%29%2Bb%26%23178%3B%EF%BC%88y-x%29+%EF%BC%9B+2-%26%23189%3Bx%26%23178%3B+%EF%BC%9B%EF%BC%88a%2B2b%EF%BC%89%26%23178%3B-4%EF%BC%88a-b%EF%BC%89%26%23178%3B%EF%BC%9B+9%EF%BC%88a%2Bb%29%26%23178%3B-4%EF%BC%88a-b%EF%BC%89%26%23178%3B%26%23178%3B%EF%BC%88%E5%B9%B3%E6%96%B9%EF%BC%89+%26%23189%3B%EF%BC%88%E4%BA%8C%E5%88%86%E4%B9%8B%E4%B8%80%EF%BC%89)
a²(x-y)+b²(y-x) ; 2-½x² ;(a+2b)²-4(a-b)²; 9(a+b)²-4(a-b)²²(平方) ½(二分之一)
a²(x-y)+b²(y-x) ; 2-½x² ;(a+2b)²-4(a-b)²; 9(a+b)²-4(a-b)²
²(平方) ½(二分之一)
a²(x-y)+b²(y-x) ; 2-½x² ;(a+2b)²-4(a-b)²; 9(a+b)²-4(a-b)²²(平方) ½(二分之一)
a²(x-y)+b²(y-x)
=(x-y)(a²-b²)
=(x-y)(a+b)(a-b)
2-½x²
=2(1- x²/4)
=2(1+½x)(1-½x)
(a+2b)²-4(a-b)²
=[(a+2b)+2(a-b)][(a+2b)-2(a-b)]
=(a+2b+2a-2b)(a+2b-2a+2b)
=3a(4b-a)
9(a+b)²-4(a-b)²
=[3(a+b)+2(a-b)][3(a+b)-2(a-b)]
=(3a+3b+2a-2b)(3a+3b-2a+2b)
=(5a+b)(a+5b)
a²(x-y)+b²(y-x)
=(x-y)(a²-b²)
=(x-y)(a+b)(a-b)
2-½x²
=1/2(4-x²)
=1/2(2+x)(2-x)
(a+2b)²-4(a-b)²
=[(a+2b)+2(a-b)][(a+2b)-...
全部展开
a²(x-y)+b²(y-x)
=(x-y)(a²-b²)
=(x-y)(a+b)(a-b)
2-½x²
=1/2(4-x²)
=1/2(2+x)(2-x)
(a+2b)²-4(a-b)²
=[(a+2b)+2(a-b)][(a+2b)-2(a-b)]
=3a(-a+4b)
=3a(4b-a)
9(a+b)²-4(a-b)²
=[3(a+b)+2(a-b)][3(a+b)-2(a-b)]
=(5a+b)(a+5b)
收起
数理答疑团为您解答,希望对你有所帮助。
a²(x-y)+b²(y-x)
=a²(x-y)-b²(x-y)
=(a²-b²)(x-y)
=(a+b)(a-b)(x-y)
2-½x²
=½(2+x)(2-x)
(a+2b)...
全部展开
数理答疑团为您解答,希望对你有所帮助。
a²(x-y)+b²(y-x)
=a²(x-y)-b²(x-y)
=(a²-b²)(x-y)
=(a+b)(a-b)(x-y)
2-½x²
=½(2+x)(2-x)
(a+2b)²-4(a-b)²
= (a+2b)²-(2a-2b)²
=(a+2b+2a-2b)(a+2b-2a+2b)
=3a(4b-a)
9(a+b)²-4(a-b)²
=(3a+3b)²-(2a-2b)²
=(3a+3b+2a-2b)(3a+3b-2a+2b)
=(5a+b)(a+5b)
祝你学习进步,更上一层楼! (*^__^*)
收起
(1)(X-y)(a^2-b^2)
(2)原式=2(1-1/4 X^2)=2[(1-(X^2 /2)]=2(1+X/2)(1-X/2)
(3)将原式的平方展开化简得12ab-3a^2=3a(4b-a)
符号很好看,怎么来的?