Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 8: 11) 81 – x2 + 4xy – 4y2 12) 12x3y – 24x2y2 + 12xy3 13) x2 – 6 x +xy – 6y 14) x3 + x2y – x2z – xyz 15) x2 – 2xy + y2 – z2 + 2zt – t

Tháng Chín 3, 2022 Toán học 2 Comments 0 views

Toán Lớp 8: 11) 81 – x2 + 4xy – 4y2
12) 12x3y – 24x2y2 + 12xy3
13) x2 – 6 x +xy – 6y
14) x3 + x2y – x2z – xyz
15) x2 – 2xy + y2 – z2 + 2zt – t2
16) x3 + y3 + 2×2 -2xy + 2y2
16) x2 – 7x + 10
17) 2×2 + 3x – 5
13) x2 – 6 x +xy – 6y
14) x3 + x2y – x2z – xyz
15) x2 – 2xy + y2 – z2 + 2zt – t2
16) x3 + y3 + 2×2 -2xy + 2y2
16) x2 – 7x + 10
17) 2×2 + 3x – 5

Comments ( 2 )

  1. giahan44
    giahan44
    3 Tháng Chín, 2022 at 9:54 chiều
    Reply
    Lời giải:
    11)
    81-x^(2)+4xy-4y^2
    =81-(x^(2)-4xy+4y^2)
    =9^(2)-(x-2y)^2
    =(9-x+2y)(9+x-2y)
    12)
    12x^(3)y-24x^(2)y^(2)+12xy^3
    =12xy.x^(2)-12xy.2xy+12xy.y^2
    =12xy.(x^(2)-2xy+y^2)
    =12xy.(x-y)^2
    13)
    x^(2)-6x+xy-6y
    =x^(2)+xy-6x-6y
    =x(x+y)-6(x+y)
    =(x+y)(x-6)
    14)
    x^(3)+x^(2)y-x^(2)z-xyz
    =x^(2)(x+y)-xz(x+y)
    =(x+y)(x^(2)-xz)
    =x(x+y)(x-z)
    15)
    x^(2)-2xy+y^(2)-z^(2)+2zt-t^2
    =(x^(2)-2xy+y^2)-(z^(2)-2zt+t^2)
    =(x-y)^(2)-(z-t)^2
    =(x-y-z+t)(x-y+z-t)
    16)
    x^(3)+y^(3)+2x^(2)-2xy+2y^2
    =(x+y)(x^(2)-xy+y^2)+2(x^(2)-xy+y^2)
    =(x^(2)-xy+y^2)(x+y+2)
    16)
    x^(2)-7x+10
    =x^(2)-5x-2x+10
    =x(x-5)-2(x-5)
    =(x-5)(x-2)
    17)
    2x^(2)+3x-5
    =2x^(2)+5x-2x-5
    =x(2x+5)-(2x+5)
    =(2x+5)(x-1)

  2. dananhnhu2k4
    dananhnhu2k4
    3 Tháng Chín, 2022 at 9:54 chiều
    Reply
    Giải đáp:
    11)(9+x-2y)(9-x+2y)
    12)12xy(x-y)^2
    13)(x-6)(x+y)
    14)x(x+y)(x-z)
    15)(x-y+z-t)(x-y-z+t)
    16)(x+y+2)(x^2-xy+y^2)
    16)(x-2)(x-5)
    17)(x-1)(2x+5)
    Lời giải và giải thích chi tiết:
    11)81-x^2+4xy-4y^2
    =81-(x^2-4xy+4y^2)
    =81-[x^2-2.x.2y+(2y)^2]
    =9^2-(x-2y)^2
    =[9+(x-2y)][9-(x-2y)]
    =(9+x-2y)(9-x+2y)
    12)12x^3y-24x^2y^2+12xy^3
    =12xy.x^2-12xy.2xy+12xy.y^2
    =12xy(x^2-2xy+y^2)
    =12xy(x-y)^2
    13)x^2-6x+xy-6y
    =(x^2-6x)+(xy-6y)
    =x(x-6)+y(x-6)
    =(x-6)(x+y)
    14)x^3+x^2y-x^2z-xyz
    =(x^3+x^2y)-(x^2z+xyz)
    =x^2(x+y)-xz(x+y)
    =(x+y)(x^2-xz)
    =x(x+y)(x-z)
    15)x^2-2xy+y^2-z^2+2zt-t^2
    =(x^2-2xy+y^2)-(z^2-2zt+t^2)
    =(x-y)^2-(z-t)^2
    =[(x-y)+(z-t)][(x-y)-(z-t)]
    =(x-y+z-t)(x-y-z+t)
    16)x^3+y^3+2x^2-2xy+2y^2
    =(x^3+y^3)+(2x^2-2xy+2y^2)
    =(x+y)(x^2-xy+y^2)+2(x^2-xy+y^2)
    =(x+y+2)(x^2-xy+y^2)
    16)x^2-7x+10
    =x^2-2x-5x+10
    =(x^2-2x)-(5x-10)
    =x(x-2)-5(x-2)
    =(x-2)(x-5)
    17)2x^3+3x-5
    =2x^2-2x+5x-5
    =(2x^2-2x)+(5x-5)
    =2x(x-1)+5(x-1)
    =(x-1)(2x+5)

Leave a reply

222-9+11+12:2*14+14 = ? ( )

Thảo

About Thảo