rut gon bieu thuc 2ax^2-a(1+2x^2)-[a-x(x+a)]
Những câu hỏi liên quan
cho A= (2x-1)^2 -5x.(x-1)+2.(x+1).(x-2) rut gon bieu thuc A
\(A=\left(2x-1\right)^2-5x\left(x-1\right)+2\left(x+1\right)\left(x-2\right)\)
\(=4x^2-4x+1-5x^2+5x+2\left(x^2-x-2\right)\)
\(=x^2-x-3\)
Cho bieu thuc A = ( 1/ x^2 - x + 1/x-1):x+1/x^2 -2x +1 ( x khac 0;1;-1)
a) Rut gon bieu thuc A
b) Tinh gia tri bieu thuc A khi x=2014/2013
c)Tim dieu kien cua x de A co gia tri lon hon 1
Mọi người tk mình đi mình đang bị âm nè!!!!!!
Ai tk mình mình tk lại nha !!!
Đúng 0
Bình luận (0)
cho 2 bieu thuc A=x+x^2/2-x va B=2x/x+1+3/x-2-2x^2+1/x^2-x-2 a, tinh gia tri cua A khi /2x-3/=1 b,tim dieu kien xac dinh va rut gon bieu thuc B c,tim so nguyen x de P=A.B dat gia tri lon nhat
mk dang can gap
a:
ĐKXĐ: x<>2
|2x-3|=1
=>\(\left[{}\begin{matrix}2x-3=1\\2x-3=-1\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}x=2\left(loại\right)\\x=1\left(nhận\right)\end{matrix}\right.\)
Thay x=1 vào A, ta được:
\(A=\dfrac{1+1^2}{2-1}=\dfrac{2}{1}=2\)
b: ĐKXĐ: \(x\notin\left\{-1;2\right\}\)
\(B=\dfrac{2x}{x+1}+\dfrac{3}{x-2}-\dfrac{2x^2+1}{x^2-x-2}\)
\(=\dfrac{2x}{x+1}+\dfrac{3}{x-2}-\dfrac{2x^2+1}{\left(x-2\right)\left(x+1\right)}\)
\(=\dfrac{2x\left(x-2\right)+3\left(x+1\right)-2x^2-1}{\left(x+1\right)\left(x-2\right)}\)
\(=\dfrac{2x^2-4x+3x+3-2x^2-1}{\left(x+1\right)\left(x-2\right)}\)
\(=\dfrac{-x+2}{\left(x+1\right)\left(x-2\right)}=-\dfrac{1}{x+1}\)
c: \(P=A\cdot B=\dfrac{-1}{x+1}\cdot\dfrac{x\left(x+1\right)}{2-x}=\dfrac{x}{x-2}\)
\(=\dfrac{x-2+2}{x-2}=1+\dfrac{2}{x-2}\)
Để P lớn nhất thì \(\dfrac{2}{x-2}\) max
=>x-2=1
=>x=3(nhận)
Đúng 0
Bình luận (0)
rut gon bieu thuc
((x^2+a)(1+a)+a^2x^2+1):((x^2-a)(1-a)+a^2x^2+1)
cm ptrinh treb ko phu thuoc vao x
rut gon bieu thuc.
A)(X^2-1).(X+2)-(X-2).(X^2+2X+4)
B)(2X+3)^2+(2X+5)^2-2.(2X+5).(2X+3)
rut gon bieu thuc
(2x-1).(x-2)
B1: rut gon bieu thuc
a, (x+y)^2-4(x-y)^2
b, 2(x-y)(x+y)+(x+y)^2+(x-y)^2
B2: tim X
a, (2X-1)^2-4(X+2)^2=9
b, 3(X-1)^2-3X(X-5)=21
B3: Cho bieu thuc
M=(x+3)^3-(x-1)^3+12x(x-1)
a, Rut gon bieu thuc tren
b, Tinh gia tri M tai x=-2/3
c, Tim x de M=16
1)a)=>x2+y2+2xy-4(x2-y2-2xy)
=>x2+y2+2xy-4.x2+4y2+8xy
=>-3.x2+5y2+10xy
Đúng 0
Bình luận (0)
rut gon bieu thuc A
A=(x/2x-4+2/2-x+1/x+2):(x-2+10-x2/x+2)
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: \(\left(3x+2\right)^2+4x-3x^2+2\left(5x-2\right)\left(5x+2\right)-75x^2\)
\(=9x^2+12x+4+4x-3x^2+50x^2-8-75x^2\)
\(=-19x^2+16x-4\)
Đúng 1
Bình luận (0)