\(\left|2x+1\right|=\left|12x-5\right|\)
\(\Rightarrow\left[{}\begin{matrix}2x+1=12x-5\\2x+1=-12x+5\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}6x=6\\14x=4\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{4}{14}=\dfrac{2}{7}\end{matrix}\right.\)
A.tính
\(25x^2-10x+1\)
B.rút gọn
\(\left(x-2\right).\left(x^2+2x+4\right)-6x^2+12x\)
(2x+5) .(5-2x)+(x-5).(5+4x)
Tìm x:
\(\frac{2x-3}{\left(7-6x\right)^2}+\frac{x-2}{\left(7-6x\right)^2}=\frac{6x-3}{\left(3x-5\right)^2}-\frac{12x-10}{\left(3x-5\right)^2}\)
Phân tích thành nhân tử:
a) \(B=\left(4x+1\right)\left(12x-1\right)\left(12x-1\right)\left(x+1\right)-4\)
b) \(C=\left(x^2+x\right)^2-2\left(x^2+x\right)-15\)
c) \(D=\left(x^2+2x\right)^2+9x^2+18x+20\)
d) \(E=\left(x^2+3x+1\right)\left(x^2+3x+2\right)-6\)
e) \(F=\left(x^2+8x+7\right)\left(x+3\right)\left(x+5\right)+15\)
\(x^2-19=5.9;\left(2x+1\right)^3=-0,001;\left(\dfrac{5}{6}\right)^{2x-1}=\left(\dfrac{5}{6}\right)^5;\left(\dfrac{1}{3}x-\dfrac{2}{3}\right)^3=27;\left(\dfrac{1}{32}\right)^x=\left(\dfrac{1}{2}\right)^{15}\)
1. Chứng minh:
\(\frac{1}{2}+\frac{1}{3\sqrt{2}}+\frac{1}{4\sqrt{3}}+\frac{1}{5\sqrt{4}}+...+\frac{1}{2016\sqrt{2015}}<\frac{88}{45}\)
2. Rút gọn: A= \(\left(\frac{1+2x}{4+2x}-\frac{x}{3x-6}+\frac{2x^2}{13-3x^2}\right)\times\frac{24-12x}{6+13x}\)
3, Cho 2x;3y tỉ lệ nghịch với 3,4;x và z tỉ lệ thuận với 4,5; x-2y+3z=1. Tính x-y-z
4. Tìm x: \(\left(2x-3\right)^2-2\left(3x+1\right)^2=2x\left(x-2\right)+\left(x-1\right)\left(x+2\right)\)
Tìm GTNN của
\(5.\left|3-12x\right|+\frac{1}{8}\)
\(\left|3x-y\right|+2.\left(y-1\right)^2-\frac{1}{5}\)
Tìm x biết
1) \(\left(2x+3\right)\left(x-4\right)+\left(x-5\right)\left(x-2\right)=\left(3x-5\right)\left(x-4\right)\)
2)\(\left(8x-3\right)\left(3x+2\right)-\left(4x+7\right)\left(x+4\right)=\left(2x+1\right)\left(5x+1\right)-33\)
3)\(6x\left(3x+5\right)-2x\left(9x-2\right)+\left(17-x\right)\left(x-1\right)+x\left(x-18\right)-17x^2=0\)
4)\(\left(x-1\right)\left(x+2\right)-\left(x-3\right)+5x-7=0\)
Giúp mình nha. Camon nhiều
Tìm x và y biết:
d)\(-1\frac{2}{3}-\left(\left|2x\right|+\frac{5}{6}\right)=\)\(-2\)e)\(\left(-\frac{1}{2}+\frac{1}{3}\right):\left|1-2x\right|-1\frac{1}{4}:\left(-\frac{5}{8}\right).\left(-\frac{1}{2}\right)^2=\frac{1}{3}\)
c)\(\left|2x-1\right|+\left|2y+1\right|+\left|2x-y\right|=0\)b)\(\left|2x-1\right|=2x-1\)
a)\(\left|x-3\right|=x+4\)
Cho 2 đa thức sau:
\(P\left(x\right)=\) \(2x^2\left(x-1\right)-5\left(x+2\right)-2x\left(x-2\right)\)
\(Q\left(x\right)=x^2\left(2x-3\right)-x\left(x+1\right)-\left(3x-2\right)\)
a.Thu gọn và sắp xếp P(x), Q(x) theo lũy thừa giảm dần của biến.
