作业帮（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²;下转（2）↓（2）[(-3m²n）²+（-mn²）³]÷（-mn）²;（3）[（3x²y+2xy²）÷xy]²；（4）[（a+b)²-（a+b)(a-b)]÷
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/16 21:56:49
![（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²;下转（2）↓（2）[(-3m²n）²+（-mn²）³]÷（-mn）²;（3）[（3x²y+2xy²）÷xy]²；（4）[（a+b)²-（a+b)(a-b)]÷](/uploads/image/z/1786645-37-5.jpg?t=%EF%BC%881%EF%BC%89%EF%BC%88%26%23189%3Bm%5E4n%5E2-1%2F3m%26%23179%3Bn%26%23178%3B-%26%23188%3Bm%26%23178%3Bn%5E4%EF%BC%89%C3%B7%EF%BC%881%2F6mn%EF%BC%89%26%23178%3B%3B%E4%B8%8B%E8%BD%AC%EF%BC%882%EF%BC%89%E2%86%93%EF%BC%882%EF%BC%89%5B%28-3m%26%23178%3Bn%EF%BC%89%26%23178%3B%2B%EF%BC%88-mn%26%23178%3B%EF%BC%89%26%23179%3B%5D%C3%B7%EF%BC%88-mn%EF%BC%89%26%23178%3B%3B%EF%BC%883%EF%BC%89%5B%EF%BC%883x%26%23178%3By%2B2xy%26%23178%3B%EF%BC%89%C3%B7xy%5D%26%23178%3B%EF%BC%9B%EF%BC%884%EF%BC%89%5B%EF%BC%88a%2Bb%29%26%23178%3B-%EF%BC%88a%2Bb%29%28a-b%29%5D%C3%B7)
（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²;下转（2）↓（2）[(-3m²n）²+（-mn²）³]÷（-mn）²;（3）[（3x²y+2xy²）÷xy]²；（4）[（a+b)²-（a+b)(a-b)]÷
（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²;下转（2）↓
（2）[(-3m²n）²+（-mn²）³]÷（-mn）²;（3）[（3x²y+2xy²）÷xy]²；（4）[（a+b)²-（a+b)(a-b)]÷（-b)；（5）[(x+y)(2x+y)+(x+y)(x-y)]÷3x
（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²;下转（2）↓（2）[(-3m²n）²+（-mn²）³]÷（-mn）²;（3）[（3x²y+2xy²）÷xy]²；（4）[（a+b)²-（a+b)(a-b)]÷
（1）（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/6mn）²
=（½m^4n^2-1/3m³n²-¼m²n^4）÷（1/36m²n²)
=（1/2乘36）m^(4-2)n^(2-2)-(1/3乘36)m^(3-2)n^(2-2)-(1/4乘36)m^(2-2)n^(4-2)
=18m²-12m-9n²
(2)
[(-3m²n）²+（-mn²）³]÷（-mn）²
=(9m^4n^2-m^3n^6)÷(m²n²)
=9m²-mn^4
(3)
[（3x²y+2xy²）÷xy]²
=(3x+2y)²
=9x²+12xy+4y²
(4)
[（a+b)²-（a+b)(a-b)]÷（-b)
=(a²+2ab+b²-a²+b²)÷(-b)
=(2b²+2ab)÷(-b)
=-2b-2a
(5)
[(x+y)(2x+y)+(x+y)(x-y)]÷3x
=(2x²+3xy+y²+x²-y²)÷3x
=(3x²+3xy)÷3x
=x+y