几条初中升高中数学衔接因式分解 求大神解决.(1)12x平方+25xy+12y平方(2)a三次方+3a平方+3a+1(3)x平方+2xy+y平方-x-y-6(4)3x三次方-7x平方+10(5)4x四次方+4x三次方-9x平方-x+2(6)x四次方+3x
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几条初中升高中数学衔接因式分解 求大神解决.(1)12x平方+25xy+12y平方(2)a三次方+3a平方+3a+1(3)x平方+2xy+y平方-x-y-6(4)3x三次方-7x平方+10(5)4x四次方+4x三次方-9x平方-x+2(6)x四次方+3x
几条初中升高中数学衔接因式分解 求大神解决.
(1)12x平方+25xy+12y平方
(2)a三次方+3a平方+3a+1
(3)x平方+2xy+y平方-x-y-6
(4)3x三次方-7x平方+10
(5)4x四次方+4x三次方-9x平方-x+2
(6)x四次方+3x三次方-3x平方-12x-4
(7)x三次方+x平方-10x-6
(8)x三次方-11x平方+31x-21
几条初中升高中数学衔接因式分解 求大神解决.(1)12x平方+25xy+12y平方(2)a三次方+3a平方+3a+1(3)x平方+2xy+y平方-x-y-6(4)3x三次方-7x平方+10(5)4x四次方+4x三次方-9x平方-x+2(6)x四次方+3x
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12x平方+25xy+12y平方
=12(x平方+y平方)+25xy
=12【(x+y)平方-2xy平方】+25xy
=12(x+y)平方-24xy+25xy
12(x+y)平方+xy
3)(x+y)平方-(x+y)-6=(x+y+2)(x+y-3)
(1)12x平方+25xy+12y平方
=(3x+4y)(4x+3y)
(2)a三次方+3a平方+3a+1
=(a+1)³
(3)x平方+2xy+y平方-x-y-6
=(x+y)²-(x+y)-6
=(x+y+2)(x+y-3)
(4)3x三次方-7x平方+10
=3x³+3x²-10x...
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(1)12x平方+25xy+12y平方
=(3x+4y)(4x+3y)
(2)a三次方+3a平方+3a+1
=(a+1)³
(3)x平方+2xy+y平方-x-y-6
=(x+y)²-(x+y)-6
=(x+y+2)(x+y-3)
(4)3x三次方-7x平方+10
=3x³+3x²-10x²+10
=3x²(x+1)-10(x²-1)
=3x²(x+1)-10(x+1)(x-1)
=(x+1)[3x²-10(x-1)]
=(x+1)(3x²-10x+10)
实数范围里已不能继续分解
=3(x+1)(x²-10x/3+10/3)
=3(x+1)[x²-10x/3+(5/3)²-25/9+30/9]
=3(x+1)[(x-5/3)²+5/9]
=3(x+1)(x-5/3+√5i/3)(x-5/3-√5i/3)
(5)4x四次方+4x三次方-9x平方-x+2
=4x^4+8x^3-4x^3-8x^2-x^2-2x+x+2
=4x³(x+2)-4x²(x+2)-x(x+2)+(x+2)
=(x+2)(4x³-4x²-x+1)
=(x+2)[(4x³-4x²)-(x-1)]
=(x+2)[4x²(x-1)-(x-1)]
=(x+2)(x-1)(4x²-1)
=(x+2)(x-1)(2x+1)(2x-1)
能不能分开问?
收起
用十字相乘因式分解法即可
如(1)3x 4y
4x 3y
原式=(3x+4y)(4x+3y)