-x2+25x-150
bằng thêm bớt hạng tử
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(-x^2-4x-3=1-\left(x^2+4x+4\right)=1-\left(x+2\right)^2=\left(1-x-2\right)\left(1+x+2\right)=\left(-x-1\right)\left(x+3\right)\)
\(=x^2-x+3x-3=x\left(x-1\right)+3\left(x-1\right)=\left(x+3\right)\left(x-1\right)\)
x⁸ + x⁴ + 1
= x⁸ + 2x⁴ + 1 - x⁴
= (x⁴ + 1)² - x⁴
= (x⁴ + 1)² - (x²)²
= (x⁴ + 1 + x²)(x⁴ + 1 - x²)
= (x⁴ + x² + 1)(x⁴ - x² + 1)
\(a,=\left(5x^3+10x\right)+\left(x^4-4\right)\\ =5x\left(x^2+2\right)+\left(x^2+2\right)\left(x^2-2\right)\\ =\left(x^2+2\right)\left(x^2+5x-2\right)\\ b,=\left(x+y\right)^3-3xy\left(x+y\right)+z^3-3xyz\\ =\left[\left(x+y\right)^3+z^3\right]-3xy\left(x+y+z\right)\\ =\left(x+y+z\right)\left[\left(x+y\right)^2-z\left(x+y\right)+z^2\right]-3xy\left(x+y+z\right)\\ =\left(x+y+z\right)\left(x^2+2xy+y-xz-yz+z^2-3xy\right)\\ =\left(x+y+z\right)\left(x^2+y^2+z^2-xy-yz-zx\right)\)
\(c,=\left(x^8+x^7+x^6\right)-\left(x^7+x^6+x^5\right)+\left(x^5+x^4+x^3\right)-\left(x^4+x^3+x^2\right)+\left(x^2+x+1\right)\\ =\left(x^2+x+1\right)\left(x^6-x^5+x^3-x^2+1\right)\\ d,=\left(x^7+x^6+x^5\right)-\left(x^6+x^5+x^4\right)+\left(x^4+x^3+x^2\right)-\left(x^3+x^2+x\right)+\left(x^2+x+1\right)\\ =\left(x^2+x+1\right)\left(x^5-x^4+x^2-x+1\right)\\ e,=\left(x^{10}+x^9+x^8\right)-\left(x^9+x^8+x^7\right)+\left(x^7+x^6+x^5\right)-\left(x^6+x^5+x^4\right)+\left(x^5+x^4+x^3\right)-\left(x^3+x^2+x\right)+\left(x^2+x+1\right)\\ =\left(x^2+x+1\right)\left(x^{10}-x^7+x^5-x^4+x^3-x+1\right)\)
a: =x^4+2x^2+5x^3+10x-2x^2-4
=(x^2+2)(x^2+5x-2)
b; =(x+y)^3+z^3-3xy(x+y)-3xyz
=(x+y+z)*(x^2+2xy+y^2-xz-yz+z^2)-3xy(x+y+z)
=(x+y+z)(x^2+y^2+z^2-xy-yz-xz)
c: =x^8+x^7+x^6-x^7-x^6-x^5+x^5+x^4+x^3-x^4-x^3-x^2+x^2+x+1
=(x^2+x+1)(x^6-x^5+x^3-x^2+1)
x4y4 + 4
= x4y4 + 4x2y2 + 4 - 4x2y2
= (x2y2 + 2)2 - (2xy)2
= (x2y2 - 2xy + 2)(x2y2 + 2xy + 2)
x4y4 + 64
= x4y4 + 16x2y2 + 64 - 16x2y2
= (x2y2 + 8)2 - (4xy)2
= (x2y2 - 4xy + 8)(x2y2 + 4xy + 8)
x5 + x + 1
= x5 - x2 + x2 + x + 1
= x2(x3 - 1) + (x2 + x + 1)
= x2(x - 1)(x2 + x + 1) + (x2 + x + 1)
= (x2 + x + 1)[x2(x - 1) + 1]
\(x^5+x+1=x^5-x^2+x^2+x+1.\)
\(=x^2\left(x^3-1\right)+x^2+x+1\)
\(=x^2\left(x-1\right)\left(x^2+x+1\right)+\left(x^2+x+1\right)\)
\(=\left(x^2+x+1\right)\left[x^2\left(x-1\right)+1\right]\)
\(=\left(x^2+x+1\right)\left(x^3-x^2+1\right)\)
\(=x^4+2x^2+1-\left(\sqrt{2}x\right)^2\)
\(=\left(x^2+1\right)^2-\left(\sqrt{2}x\right)^2\)
\(=\left(x^2+1-\sqrt{2}x\right)\left(x^2+1+\sqrt{2}x\right)\)
\(x^4+1\)
\(=x^4+2x^2+1-2x^2\)
\(=\left(x^2+1\right)^2-\left(x\sqrt{2}\right)^2\)
\(=\left(x^2-x\sqrt{2}+1\right)\left(x^2+x\sqrt{2}+1\right)\)
\(x^4+1\)
\(=x^4+2x^2+1-2x^2\)
\(=\left(x^2+1\right)^2-2x^2\)
\(=\left(x^2-\sqrt{2}x+1\right)\left(x^2+\sqrt{2}x+1\right)\)
\(-x^2+25x-150=-\left(x^2-25x+\dfrac{625}{4}\right)+\dfrac{625}{4}-150=\dfrac{25}{4}-\left(x-\dfrac{25}{2}\right)^2=\left(\dfrac{5}{2}-x+\dfrac{25}{2}\right)\left(\dfrac{5}{2}+x-\dfrac{25}{2}\right)=\left(15-x\right)\left(x-10\right)\)
`-x^2+25x-150`
`=-(x^2-25x+150)`
`=-(x^2-10x-15x+150)`
`=-[x(x-10)-15(x-10)]`
`=-(x-10)(x-15)`