giải pt:
a) x4 + 2x3 -12x2 -13x +42
b) (x -1) (x+2 )(x+4)(x+7)=16
c) x4 + 2x3 +5x2 +4x -12 = 0
Phân tích
a,(x2 + x + 2)3 - (x+1)3 = x6 +1 b,(x2 + 10x + 8)2 - (8x + 4)(x2 + 8x+7)
c, A= x4 + 2x3 + 3x2 + 2x+4 d,B= x4 + 4x3 + +8x2 + 8x + 4
e, C= x4 - 2x3 + 5x2 - 4x + 4
Giải phương trình:
a) x4 - 2x3 + x2 - 4x +4 = 0
b) x4 + 2x3 - 3 = 0
c) 2x4 - 100x + 98 = 0
d) (x + 1)(x + 2)(x + 3)(x + 4) = 24
d: Ta có: \(\left(x+1\right)\left(x+2\right)\left(x+3\right)\left(x+4\right)=24\)
\(\Leftrightarrow\left(x^2+5x+4\right)\left(x^2+5x+6\right)-24=0\)
\(\Leftrightarrow x\left(x+5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-5\end{matrix}\right.\)
A(x)=x4+2x3-5x2-3x-6
B(x)=-x4-2x3+5x2+x+10
a/Tìm đa thức M(x) sao cho B(x)-M(x)=A(x)
a) Ta có: B(x)-M(x)=A(x)
nên M(x)=B(x)-A(x)
\(=x^4-2x^3+5x^2+x+10-x^4-2x^3+5x^2+3x+6\)
\(=-4x^3+10x^2+4x+16\)
F(x)=x4+5x2-4x+x5-x4-8x2+3+2x3+2
Thu gọn và sắp xếp phải k ạ?
`F(x)= (x^4-x^4)+(5x^2-8x^2)-4x+x^5+3+2x^3+2`
`F(x) = -3x^2-4x+x^5+3+2x^3+2`
`F(x)= x^5+2x^3-3x^2-4x+3+2`
\(F\left(x\right)=x^4+5x^2-4x+x^5-x^4-8x^2+3+2x^3+2\)
\(F\left(x\right)=x^5+\left(x^4-x^4\right)+2x^3+\left(5x^2-8x^2\right)-4x+\left(3+2\right)\)
\(F\left(x\right)=x^5+2x^3-3x^2-4x+5\)
Bài toán 3 : Thực hiện phép chia.
a) (2x3 – 5x2 – x + 1) : (2x + 1)
b) (x3 – 2x + 4) : (x + 2)
c) (6x3 – 19x2 + 23x – 12) : (2x – 3)
d) (x4 – 2x3 – 1 + 2x) : (x2 – 1)
a: \(\dfrac{2x^3-5x^2-x+1}{2x+1}\)
\(=\dfrac{2x^3+x^2-6x^2-3x+2x+1}{2x+1}\)
\(=x^2-3x+1\)
b: \(\dfrac{x^3-2x+4}{x+2}\)
\(=\dfrac{x^3+2x^2-2x^2-4x+2x+4}{x+2}\)
\(=x^2-2x+2\)
a) (35x3 + 41x2 + 13x – 5) : (5x – 2)
b) (27x3 - 8) : (2x – 3)
c) (3x4 – 2x3 – 5x2 – 3) : (x2 + 2x – 2)
d) (x4 – x 3y + x2y 2 – xy3 ) : (x2 + y2 )
a: \(=\dfrac{35x^3-14x^2+55x^2-22x+35x-14+9}{5x-2}\)
\(=7x^2-11x+7+\dfrac{9}{5x-2}\)
b: \(=\dfrac{\left(2x-3\right)\left(4x^2+6x+9\right)}{2x-3}=4x^2+6x+9\)
a)(-3x2+5x2-9x+15):(-3x+5)
b)(x4-2x3+2x-1):(x2-1)
c)(5x4+9x3-2x2-4x-8):(x-1)
d)(5x3+14x2+12x+8):(x+2)
b: \(\dfrac{\left(x^2-1\right)\left(x^2+1\right)-2x\left(x^2-1\right)}{x^2-1}\)
\(=x^2-2x+1\)
\(=\left(x-1\right)^2\)
c: \(=\dfrac{5x^4-5x^3+14x^3-14x^2+12x^2-12x+8x-8}{x-1}\)
\(=5x^3+14x^2+12x+8\)
Giup mik với :
C1/.x4+2x3-4x-4 C2/ x(x+2y)3-y(2x+y)3 C3/. x4- 30x2+31x-30 C4/. 60x+18x2- 6x3 C5/. x4+6x+8 C6/. x4- 5x2+x3 -5x
Cho f(x)= x 4 - 2 x 3 - 5 x 2 + 2 x + 1 24 ( x - 1 )
Tính f ( 4 ) (2) (Đạo hàm bậc 4 của f(x) tại (2).
A. -72
B. 1/24
C. -3
D. 16
thực hiện phép chia
(-3x3 + 5x2 - 9x + 15) : (-3 + 5)
(x4 - 2x3 + 2x -1) : (x2 - 1)
(5x4 + 9x3 - 2x2 - 4x -8) : (x-1)
(5x3 + 14x2 + 12x + 8) : (x+2)
c) Ta có: \(\dfrac{5x^4+9x^3-2x^2-4x-8}{x-1}\)
\(=\dfrac{5x^4-5x^3+14x^3-14x^2+12x^2-12x+8x-8}{x-1}\)
\(=\dfrac{5x^3\left(x-1\right)+14x^2\left(x-1\right)+12x\left(x-1\right)+8\left(x-1\right)}{x-1}\)
\(=5x^3+14x^2+12x+8\)
d) Ta có: \(\dfrac{5x^3+14x^2+12x+8}{x+2}\)
\(=\dfrac{5x^3+10x^2+4x^2+8x+4x+8}{x+2}\)
\(=\dfrac{5x^2\left(x+2\right)+4x\left(x+2\right)+4\left(x+2\right)}{x+2}\)
\(=5x^2+4x+4\)