Tuyển Cộng tác viên Hoc24 nhiệm kì 26 tại đây: https://forms.gle/dK3zGK3LHFrgvTkJ6
Rut gon
a,(4x-7)(16x^2+28x+49)
b,(3x+1)(9x^2-3x+1)-9x(3x^2-1)
rut gon bieu thuc :
\(\left(x+1\right)^4-6\left(x+1\right)^2-\left(x^2-2\right).\left(x^2+2\right)\)
rut gon bieu thuc
(a+b-c)^2 - (a-c)^2- 2ab+ 2bc
rut gon
a)(2x+1)^2+2(4x^2-1)+(2x-1)^2
b)(x+y+z)^2+(x-y)^2+(x-y)^2+(y-z)^2-(x^2+y^2+z^2)
c)(a+b+c)^2-2(a+b+c)(b+c)+(b+c)^2
rut gon cac bt
(x2-xy+y2)(x2+xy+y2)
1) Rut gon cac bieu thuc sau :
a) (x-3)(x2+3x+ 9)-(54+x3)
b) (3x+y)(9x2-3xy +y2)-(3x-y)(9x2+3xy+y2)
2) Chung minh rang:
a) a3+b3= (a+b)3 -3ab(a+b)
b) a3-b3=(a-b)3 +3ab(a-b)
Ap dung : Tinh a3+b3 biet ab=12va a+b =-7
nhah nha mk dang can rat gap
bài 1:
a)7x(x2-7x+3) b)(x+6)(x-7)
c)(x-8)2 d) (3x+2)2
e)(x-4)(x+4)-(5-x)2
Bài 2:
a)2(x-7)-9=10 b)(2x-5)2-x(4x-3)=2x+50
1) Rut gon cac bieu thuc sau :
a) (x-3)(x2+3x+ 9)-(54+x3)
b) (3x+y)(9x2-3xy +y2)-(3x-y)(9x2+3xy+y2)
2, Dien cac don thuc thich hop vao cho trong
a, (x+3y) (... - ... + ...) = x^3 +27y^3
b, (2x- ....) (... + 6xy + ... +...) = 8x^3 - 27y^3
rut gọn rồi tinh gia trị của cac biểu thưc
a)A =(x+y)^2+(x-y^2)+2(x+y(x-y) vơi x=1/2,y=-3
b)P=x^3+3x^2+3x+1 vơi x+99
c)Q=(x^3+6x^2)+12x+8)+3(x^2+4x+4)y+3(x+2)y^2
+y^3 vơi x+y=8
