rut gon bieu thuc (6x+7)(2x-3)-(4x+1)(3x-7/4)
(4x-3)(3x+2)-(6x+1)(2x-5)+1
rut gon bieu thuc
12x2 + 8x - 9x - 6 - 12x2 + 30x + 2x -5 + 1= 31x - 10
Rut gon bieu thuc sau: 2x*(2x-1)2-3x*(x+3)2-4x*(x+1)2
rut gon cac bieu thuc
2x(2x+1)2 - 3x(x+3)(x-3) - 4x (x+1) 2
Ta có 2x(2x + 1)2 - 3x(x + 3)(x - 3) - 4x(x + 1)2
= 2x(4x2 + 4x + 1) - 3x(x2 - 9) - 4x(x2 + 2x + 1)
= 8x3 + 8x2 + 2x - 3x3 + 27x - 4x3 - 8x2 - 4x
= 8x3 - 3x3 - 4x3 + 8x2 - 8x2 + 2x + 27x - 4x
= x3 + 25x
a oi hinh nhu sai r con +16x2 nua co a , anh tinh lai ho e duoc kh
Kiều Trinh Vũ ko có + 16x2 nhá vì 8x2 - 8x2 = 0 nhá
cho bieu thuc A = /x-1/ + 3x-7
a. rut gon bieu thuc
b. tinh A khi x=3;x=-5
rut gon bieu thuc a,(3x+2)^2+4x-3^2+2(5x-2)(5x+2)-75x^2
b,(x-2)^3+(2x+1)^3++2(x+2)(1-x)-9x^3+2x
a: \(\left(3x+2\right)^2+4x-3x^2+2\left(5x-2\right)\left(5x+2\right)-75x^2\)
\(=9x^2+12x+4+4x-3x^2+50x^2-8-75x^2\)
\(=-19x^2+16x-4\)
Rut gon bieu thuc:
2(2x-3)^2+(x-2)(x+2)
(12x^2y^2-6x^3y^2):3x^2y:-4y(2x-5)
Rut gon cac bieu thuc sau
A) 2x^2(1-3x)+6x^3
B) (x-y)^2+(x+y)^2+2(x-y)(x+y)
A) 2x2(1-3x)+6x3
=2x2*(1-3x)+2x2*3x
=2x2*(1-3x+3x)
=2x2
B) (x-y)2+(x+y)2+2(x-y)(x+y)
=2(x2-y2)+x2+2xy+y2+x2-2xy+y2
=2x2-2y2+x2+2xy+y2+x2-2xy+y2
=4x2
Rut gon cacc bieu thuc sau : ( 4x - 3 ).( x - 5 ) - 2x ( 2x- 11)
\(\left(4x-3\right).\left(x-5\right)-2x\left(2x-11\right)\)
=\(4x^2-20x-3x+15-\left(4x^2-22x\right)\)
\(=4x^2-20x-3x+15-4x^2+22x\)
\(=-x+15\)
Rut gon cac bieu thuc sau:
2(x-y).(x+y)+(x-y)^2+(x+y)^2
(2x-3).(4x^2+6x+9) -(54+8x)
(3x+y).(9x^2-3xy+y^2)-(3x-y).(9x^2+3xy+y^2)
(a +b +c)^2-(a-c)^2-2ab+2bc
\(a,\)\(2\left(x-y\right)\left(x+y\right)+\left(x-y\right)^2+\left(x+y\right)^2.\)
\(=\left[\left(x-y\right)+\left(x+y\right)\right]^2=\left(x-y+x+y\right)^2=x^2\)
\(b,\)\(\left(2x-3\right)\left(4x^2+6x+9\right)-\left(54+8x\right)\)
\(=8x^2-27-54-8x=8x^2-8x-81\)
\(c,\)\(\left(3x+y\right)\left(9x^2-3xy+y^2\right)-\left(3x-y\right)\left(9x^2+3xy+y^2\right)\)
\(=27x^3+y^3-\left(27x^3-y^3\right)=2y^3\)
\(d,\)\(\left(a+b+c\right)^2-\left(a-c\right)^2-2ab+2bc\)
\(=a^2+b^2+c^2+2ab+2bc+2ac-a^2+2ac-c^2-2ab+2bc\)
\(=b^2+4bc+4ac\)