3x^3-6x^2+3x giúp mik vs
Các bạn giúp mik vs nha:
a, x^3-7x-6
b, x^3+3x^2-4
c, x^3+3x^2+6x+18
d, 2x^3-3x^2+3x-1
e, 2x^3+3x^2+8x-12
CÁC BN GIÚP MIK VS NHA!!!CẢM ƠN NHÌU NEK!!!^-^!!!
giải giúp mik vs<3
(6x-2)²+(5x-2)²-4(3x-1)(5x-2)=0
\(\Leftrightarrow\left(6x-2\right)^2+\left(5x-2\right)^2-2\left(6x-2\right)\left(5x-2\right)=0\)
\(\Leftrightarrow\left[\left(6x-2\right)-\left(5x-2\right)\right]^2=0\)
\(\Leftrightarrow x^2=0\)
\(\Leftrightarrow x=0\)
3x-2/x+7=6x+1/2x-3 giúp mik vs ae ơi
Mn giúp mik vs nha, mik đg cần rất rất là gấp😢😢😢
- Thực hiện phép nhân đơn thức vs đa thức
a) xy (x^2 + 3x)
b) -4 (6x^2 - xy)
c) 4x [x^2 + 6x - 1 phần 2]
- rút gọn biểu thức
a) 2x (x^2 + 3x) -2 (x^3 - 4 + 3x^2)
b) 2x (5x + 2) - (10x^2 + 4x + 1)
Mn dễ thương giúp mik nha😍😍😍
Giúp mik vs mn ơi
Tìm GTLN của A=-x^2+3x-5 B=5x-4x^2-3 C=5-4x-25x^2 D=3x-2x^2 E=2+6x-1/4x^2 F=-5x^2+4x
\(A=-x^2+3x-5\)\(=-\dfrac{11}{4}-\left(x^2-2.\dfrac{3}{2}x+\dfrac{9}{4}\right)=-\dfrac{11}{4}-\left(x-\dfrac{3}{2}\right)^2\le-\dfrac{11}{4}\) với mọi x
\(\Rightarrow A_{max}=-\dfrac{11}{4}\Leftrightarrow x-\dfrac{3}{2}=0\Leftrightarrow x=\dfrac{3}{2}\)
\(B=5x-4x^2-3=-\dfrac{23}{16}-\left(4x^2-2.\dfrac{5}{4}.2x+\dfrac{25}{16}\right)\)\(=-\dfrac{23}{16}-\left(2x-\dfrac{5}{4}\right)^2\)\(\le-\dfrac{23}{16}\forall x\)
\(\Rightarrow B_{max}=-\dfrac{23}{16}\Leftrightarrow2x-\dfrac{5}{4}=0\Leftrightarrow x=\dfrac{5}{8}\)
\(C=5-4x-25x^2=\dfrac{129}{25}-\left(25x^2+2.5x.\dfrac{2}{5}+\dfrac{4}{25}\right)\)\(=\dfrac{129}{25}-\left(5x+\dfrac{2}{5}\right)^2\le\dfrac{129}{25}\forall x\)
\(\Rightarrow C_{max}=\dfrac{129}{25}\Leftrightarrow5x+\dfrac{2}{5}=0\Leftrightarrow x=-\dfrac{2}{25}\)
\(D=3x-2x^2=-2\left(x^2-\dfrac{3}{2}x\right)=-2\left(x^2-2.\dfrac{3}{4}x+\dfrac{9}{16}\right)+\dfrac{9}{8}\)\(=\dfrac{9}{8}-2\left(x-\dfrac{3}{4}\right)^2\le\dfrac{9}{8}\) với mọi x
\(\Rightarrow D_{max}=\dfrac{9}{8}\Leftrightarrow x-\dfrac{3}{4}=0\Leftrightarrow x=\dfrac{3}{4}\)
\(E=2+6x-\dfrac{1}{4}x^2=-\dfrac{1}{4}\left(x^2-24x\right)+2=-\dfrac{1}{4}\left(x^2-2.12x+144\right)+38\)\(=38-\dfrac{1}{4}\left(x-12\right)^2\le38\forall x\)
\(\Rightarrow E_{max}=38\Leftrightarrow x-12=0\Leftrightarrow x=12\)
\(F=-5x^2+4x=-5\left(x^2-\dfrac{4}{5}x\right)=-5\left(x^2-2.\dfrac{2}{5}x+\dfrac{4}{25}\right)+\dfrac{4}{5}\)\(=\dfrac{4}{5}-5\left(x-\dfrac{2}{5}\right)^2\le\dfrac{4}{5}\forall x\)
\(\Rightarrow F_{max}=\dfrac{4}{5}\Leftrightarrow x-\dfrac{2}{5}=0\Leftrightarrow x=\dfrac{2}{5}\)
Tìm thương của phép chia: [9x^3 (x^2 - 1) − 6x^2 (x^2 - 1)^2 + 12x(x^2 -1)]: 3x(x^2 - 1). Giúp mik vs, mik cần gấp!!
[9x³(x² - 1) - 6x²(x² - 1) + 12x(x² - 1)] : 3x(x² - 1)
= [9x³(x² - 1) : 3x(x² - 1)] - [6x²(x² - 1) : 3x(x² - 1) + [12x(x² - 1) : 3x(x² - 1)]
= 3x² - 2x + 4
Tìm x, biết:
a) (2x+2)(x-1)-(x+2)(2x+1)=0;
b)(3x+1)(2x-3)-6x(x+2)=16;
c)(12x-5)(4x-1)+(3x-7)(1-16x)=81
mn ơi giúp mik vs ạ :<
a: =>2x^2-2x+2x-2-2x^2-x-4x-2=0
=>-5x-4=0
=>x=-4/5
b: =>6x^2-9x+2x-3-6x^2-12x=16
=>-19x=19
=>x=-1
c: =>48x^2-12x-20x+5+3x-48x^2-7+112x=81
=>83x=83
=>x=1
Giúp mik vs
Tích của (2x2n + 3x2n-1)( x1-2n - 3x2-2n) là:
A. 6x2 - 7x+3
B. - 6x2 +7x+3
C. - 6x2 - 7x -3
D. - 6x2 - 7x +3
2 . ( x³ -1)-2x²(x+2x⁴) +(4x⁵+4)x=6. 3. (X²-4x+16)(x+4)-x(x+1)(x+2)+3x²= 0 4 . ( 8x +2 ) (1-3x) + ( 6x-1)(4x-10) =-50 Đề bài là tìm x nha mn Nhanh giúp mik vs
2:
=>x^3-1-2x^3-4x^6+4x^6+4x=6
=>-x^3+4x-7=0
=>x=-2,59
4: =>8x-24x^2+2-6x+24x^2-60x-4x+10=-50
=>-62x+12=-50
=>x=1