viet cac bieu thuc sau duoi dang tich:
a, 27x\(^3\)-27x\(^2\)+3x+1
b,x\(^3\)-3x\(^2\)+3x-1
c,\(\dfrac{1}{27}\)+x\(^3\)
d, 0,001-1000x\(^3\)
viet cac bieu thuc sau duoi dang tich:
a, 27x\(^3\)-27x\(^2\)+3x+1
b,x\(^3\)-3x\(^2\)+3x-1
c,\(\dfrac{1}{27}\)+x\(^3\)
d, 0,001-1000x\(^3\)
viet cac bieu thuc sau duoi dang tich:
a, 27x\(^3\)-27x\(^2\)+3x+1
b,x\(^3\)-3x\(^2\)+3x-1
c,\(\dfrac{1}{27}\)+x\(^3\)
d, 0,001-1000x\(^3\)
a: Sửa đề: \(27x^3-27x^2+9x-1\)
\(=\left(3x-1\right)^3\)
b: \(=\left(x-1\right)^3\)
c: \(=\left(x+\dfrac{1}{3}\right)\left(x^2-\dfrac{1}{3}x+\dfrac{1}{9}\right)\)
Viết biểu thức sau dưới dạng tích:
a, 27x3-27x2+3x+1
b. x3 - 3x2+3x-1
c, \(\frac{1}{27}\)+x3
d, 0,001-1000x3
a) (3x-1)3 Xem lại đề câu a là -1
b) (x-1)3
c) (1/3 + x)(1/9 -x.1/3 +x2)
d) (0,1-10x)(0,01 + x +100x2)
27x^3 - 27 x^2 +3x - 1
1/27 + x^3
x^3- 3x^2+3x-1
0,001-1000x^3
12/5 x^2y^2-9x^4 - 4/25y^4
a^2y^2+b^2x^2-2axby
100-(3x-y)^2
64x^2-(8a+b)^2
27x^3-a^3b^3
b: \(x^3+\dfrac{1}{27}=\left(x+\dfrac{1}{3}\right)\left(x^2-\dfrac{1}{3}x+\dfrac{1}{9}\right)\)
c: \(x^3-3x^2+3x-1=\left(x-1\right)^3\)
e: \(a^2y^2-2axby+b^2x^2\)
\(=\left(ay\right)^2-2\cdot ay\cdot bx+\left(bx\right)^2\)
\(=\left(ay-bx\right)^2\)
f: \(100-\left(3x-y\right)^2\)
\(=\left(10-3x+y\right)\left(10+3x-y\right)\)
g: \(64x^2-\left(8a+b\right)^2\)
\(=\left(8x\right)^2-\left(8a+b\right)^2\)
\(=\left(8x-8a-b\right)\left(8x+8a+b\right)\)
Viết bt sau dưới dạng tích :
a)27x3-27x2+3x+1
b)x3-3x2+3x-1
c)0,001-1000x3
TT giúp mik nha
Viết các BT sau dưới dạng tích:
a, 27x^3- 27x^2+ 3x+ 1
b, x^3- 3x^2+ 3x- 1
c, 1/27+ x^3
d, 0,001- 1000x^3
Làm hộ mk nha. Thanks!
a) \(27x^3-27x^2+3x+1=27x^3-9x^2-18x^2+6x-3x+1\)
\(=\left(27x^3-9x^2\right)- \left(18x^2-6x\right)-\left(3x-1\right)\)
\(=9x^2\left(3x-1\right)-6x\left(3x-1\right)-\left(3x-1\right)\)
\(=\left(3x-1\right)\left(9x^2-6x-1\right)\)
b) \(x^3-3x^2+3x-1=x^3-3.x^2.2+3.x.1^2-1^3=\left(x-1\right)^3\)
c) \(\frac{1}{27}+x^3=\left(\frac{1}{3}\right)^3+x^3=\left(x+\frac{1}{3}\right)\left[\left(\frac{1}{3}\right)^2-\frac{1}{3}.x+x^2\right]=\left(x+\frac{1}{3}\right)\left(x^2-\frac{1}{3}x+\frac{1}{9}\right)\)
d) \(0,001-1000x^3=\left(\frac{1}{10}\right)^3-\left(10x\right)^3=\left(\frac{1}{10}-10x\right)\left[\left(\frac{1}{10}\right)^2+\frac{1}{10}.10x+\left(10x\right)^2\right]\)
\(=\left(\frac{1}{10}-10x\right)\left(100x^2+x+\frac{1}{100}\right)\)
Tìm x
a, (x+2)^3 - x(x^2+6x-3)=0
b,(x+4)^3 - x(x+6)^2=7
c, (x-1)^3 - x(x^2-3x-2)=0
d,1000x^3+90x(10x+3)+27=0
e,125x^3+15x(5x+1)= -1
f, 27x^3+45x(3x+5)+133=0
a, \(\left(x+2\right)^3-x\left(x^2+6x-3\right)=0\Leftrightarrow x^3+4x^2+4x+2x^2+8x+8-x^3-6x^2+3x=0\)
\(\Leftrightarrow15x+8=0\Leftrightarrow x=-\frac{8}{15}\)
b, \(\left(x+4\right)^3-x\left(x+6\right)^2=7\Leftrightarrow12x+64=0\Leftrightarrow x=-\frac{19}{4}\)làm tắt:P
Tự làm nốt nhé
viet cac bieu thuc sau duoi dang tong:
a,(-3x+2)\(^3\)
\(a,\left(-3x+2\right)^3\)
\(=\left(2-3x\right)^3\)
\(=2^3-3.2^2.3x+3.2.9x^2-27x^3\)
\(=8-36x+54x^2-27x^3\)
viet cac bieu thuc sau duoi dang tong:
a,(-3x+2)\(^3\)
\(a,\left(-3x+2\right)^3=\left(2-3x\right)^3=2^3-3.2^2.3x+3.2.9x^2-27x^3=8-36x+54x^2-27x^3\)