设y kx,是否存在实数k,使得代数式(见下图),能化简为x

2021-02-25 08:57:39 字数 2154 阅读 5198

1楼:我不是他舅

^原式=(4x2-y2)(x2-y2+3x2)=(4x2-y2)2

则bai(4x2-k2x2)2=x^du4(4-k2)2*x^4=x^4

所以zhi

dao(4-k2)2=1

4-k2=±1

k2=3或5

所以k=-√

专5,属k=√5,k=-√3,k=√3

设y=kx,是否存在实数k,使得代数式(x2-y2)(4x2-y2)+3x2(4x2-y2)能化简为x4?若能,请求出所有满足

2楼:匿名用户

能;(x2-y2)(4x2-y2)+3x2(4x2-y2)=(4x2-y2)(x2-y2+3x2)

=(4x2-y2)2,

当y=kx,原式=(4x2-k2x2)2=(4-k2)2x4,令(4-k2)2=1,解得k=±3或±

5,即当k=±3或±

5时,原代数式可化简为x4.

设y=kx,是否存在实数k,使得代数式(x2-y2)(4x2-y2)+3x2(4x2-y2)能化简

3楼:过分丶正义

^把袭y=kx代入(x^bai2-y^du2)(4x^2-y^2)+3x^2(4x^2-y^2)=(4x^2-y^2)^2得

[(4-k^2)x^2]^2=x^4,

∴zhi(4-k^2)^2=1,

∴k^2-4=土1,

∴k^2=5,或3,

∴k=土√

dao5或土√3.

设y=kx,是否存在实数k,使代数式(x的平方减y的平方)(4x的平方减y的平方)+3x的平方乖(

4楼:vicky繁

能;(baix2-y2)(4x2-y2)+3x2(du4x2-y2)=(4x2-y2)(x2-y2+3x2)

=(4x2-y2)2,zhi

当y=kx,原式=(4x2-k2x2)2=(4-k2)2x4,令(4-k2)2=1,

解得k=±3或±5,

即当daok=±3或±5时,

原代数式可化简为x4.

设y=kx,是否存在有理数k,使得代数式(x-y)(4x-y)+3x(4x-y)能化简成x2?若能

5楼:匿名用户

^^y=kx

(x-y)(4x-y)+3x(4x-y)

=4x^bai2-5xy+y^2+12x^2-3xy=16x^2-8xy+y^2

=16x^2-8x(kx)+(kx)^2

=16x^2-8kx^2+k^2x^2

=(16-8k+k^2)x^2

要使(x-y)(4x-y)+3x(4x-y)= x^2即:du(16-8k+k^2)x^2= x^216-8k+k^2=1

k^2-8k+15=0

(k-3)(k-5)=0

k=3或者k=5

当k=3或者k=5时zhi,代数式(x-y)(4x-y)+3x(4x-y)能化

dao简成x^2。

6楼:赚大钱

(x-y)(4x-y)+3x(4x-y)=(4x-y)(x-y

+3x)=(4x-y)2,把y=kx代入,得(4-k)2x2,所以4-k=1,k=3

设y=kx,是否存在实数k,使得(x^2-y^2)(4x^2-y^2)+3x^2(4x^2-y^2

7楼:琉璃易碎

^^^把y=kx代入(x^2-y^2)(4x^2-y^2)+3x^2(4x^2-y^2)=(4x^2-y^2)^2得

[(4-k^2)x^2]^2=x^4,

∴(4-k^2)^2=1,

∴k^2-4=土内1,

∴k^2=5,或3,

∴k=土√

容5或土√3.

8楼:我非柠檬

^把y=kx代入(x^bai2-y^2)(4x^du2-y^zhi2)+3x^2(4x^2-y^2)=(4x^2-y^2)^2得:[(4-k^2)x^2]^2=x^4,

∴(4-k^2)^2=1,

∴k^2-4=土1,dao

∴k^2=5,或3,

∴k=土√5或土√3