在线等初2数学题

来源:百度知道 编辑:UC知道 时间:2024/07/06 19:00:49
(2x-1)^4=(a4)x^4+(a3)x^3+(a2)x^2+(a1)x+(a0)
1. (a4)+(a3)+(a2)+(a1)+(a0)的值
2. (a4)-(a3)+(a2)-(a1)+(a0)的值
3. (a4)+(a2)+(a0)的值

(1)
取x=1代入,得:
(2-1)^4 = a0+a1+a2+a3+a4 =1…………①

(2)
取x=-1代入,得:
(-2-1)^4= a0-a1+a2-a3+a4 = -243…………②
② + ①,得:
2(a2+a4+a0) = -243+1 = -242
所以:
a1+a3+a5 = -121

初二还是高二

1. (a4)+(a3)+(a2)+(a1)+(a0)=1 ……①
取x=-1代入,可得
2. (a4)-(a3)+(a2)-(a1)+(a0)=81……②
取x=-1代入,可得
3. (a4)+(a2)+(a0)=41
② + ①,得:
2(a2+a4+a0) = 81+1 = 82
所以(a4)+(a2)+(a0)=41

1,将x=1代入原式,就是(1),(a4)+(a3)+(a2)+(a1)+(a0)=1
2.将x=-1代入原式(a4)-(a3)+(a2)-(a1)+(a0)=81
3.将上两小题的答案相加除以二,就是 (a4)+(a2)+(a0)=41

(2X-1)^4=[(2X-1)^2]^2
=(4X^2-4X+1)^2
=(4X^2-4X)^2+2(4X^2-4X)+1
=16X^4-16X^3+16X^2+8X^2-8X+1
=16X^4-16X^3+24X^2-8X+1
a4=16,a3=16,a2=24,a1=-8,a0=1
1.(a4)+(a3)+(a2)+(a1)+(a0)=16+16+24-8+1=49
2.(a4)-(a3)+(a2)-(a1)+(a0)=16-16+24+8+1=33
3.(a4)+(a2)+(a0)=16+24+1=41

(2x-1)^4=(4x^2-(4x-1))^2
=16x^4-2*4x^2*(4x-1)+(4x-1)^2
=16x^4-8x^2(4x-1)