\(\Leftrightarrow2^{-3\left(-x^2+x\right)}=2^{-3x+\dfrac{1}{3}}\)
\(\Leftrightarrow3x^2-3x=-3x+\dfrac{1}{3}\)
\(\Leftrightarrow3x^2=\dfrac{1}{3}\)
hay \(x\in\left\{\dfrac{1}{3};-\dfrac{1}{3}\right\}\)
\(\Leftrightarrow2^{-3\left(-x^2+x\right)}=2^{-3x+\dfrac{1}{3}}\)
\(\Leftrightarrow3x^2-3x=-3x+\dfrac{1}{3}\)
\(\Leftrightarrow3x^2=\dfrac{1}{3}\)
hay \(x\in\left\{\dfrac{1}{3};-\dfrac{1}{3}\right\}\)
Giải các phương trình sau:
\(e.\dfrac{12}{1-9x^2}=\dfrac{1-3x}{1+3x}-\dfrac{1+3x}{1-3x}\)
\(f.\dfrac{6x+1}{x^2-7x+10}+\dfrac{5}{x-2}=\dfrac{3}{x-5}\)
\(g.\dfrac{2}{x+2}-\dfrac{2x^2+16}{x^3+8}=\dfrac{5}{x^2-2x+4}\)
\(h.\dfrac{8}{x-8}+\dfrac{11}{x-11}=\dfrac{9}{x-9}+\dfrac{10}{x-10}\)
\(A=\left(\dfrac{4x}{x+2}-\dfrac{x^3-8}{x^3+8}\times\dfrac{4x^2-8x+16}{x^2-4}\right)\div\dfrac{16}{x+2}\times\dfrac{x^2+3x+2}{x^2+x+1}\)
\(B=\dfrac{x^2+x-2}{x^3-1}\)
a) Tìm ĐKXĐ của A, B. Rút gọn A, B
b)Tìm GTLN của A+B
tìm x biết:
a, (x - 1)3 + (2 - x) (4 + 2x + x2) + 3x (x + 2) = 16
b, 8 (x - \(\dfrac{1}{2}\)) (x2 + \(\dfrac{1}{2}\)x + \(\dfrac{1}{4}\)) - 4x (1 - x - 2x2) = - 2
\(\dfrac{3}{x-5}-\dfrac{x+1}{x\left(x-5\right)}\)
\(\dfrac{8\left(y+2\right)}{3x^2}.\dfrac{15x^5}{4\left(y+2\right)^2}\)
\(\dfrac{8\left(y-1\right)}{3x^2-3}:\dfrac{4\left(y-1\right)^3}{x^2-2x+1}\)
cho biểu thức: P=\((\dfrac{x^2 +3x+2}{x^2 +x-2}-\dfrac{x^2-x}{x^2-1}):(\dfrac{1}{x+1}+\dfrac{1}{x-1})\)
a, Rút gọn P
b, tìm x để \(\dfrac{1}{P}-\dfrac{x+1}{8}\)≥1
Thực hiện phép tính:
a) \(\dfrac{x}{2x-y}-\dfrac{2x-y}{4x-2y}\)
b)\(\dfrac{3x+1}{x^2-1}-\dfrac{x}{2x-2}\)
c) \(\dfrac{x-2}{x^2-4}-\dfrac{-8-x}{3x^2+6x}\)
d) \(\dfrac{2}{2x-3}-\dfrac{x}{2x+3}-\dfrac{2x+1}{9-4x^2}\)
Bài 1)tìm Min hay Max
a) G=\(\dfrac{2}{x^2+8}\)
b) H=\(\dfrac{-3}{x^2-5x+1}\)
Bài 2) Tìm Min hay Max
a)D=\(\dfrac{2x^2-16x+41}{x^2-8x+22}\)
b)E=\(\dfrac{4x^4-x^2-1}{\left(x^2+1\right)^2}\)
c)G=\(\dfrac{3x^2-12x+10}{x^2-4x+5}\)
1/ \(\dfrac{5x+1}{8}-\dfrac{x-2}{4}=\dfrac{1}{2}\)
2/ \(\dfrac{x+3}{4}+\dfrac{1-3x}{3}=\dfrac{-x+1}{18}\)
3/ \(\dfrac{x+2}{4}-\dfrac{5x}{6}=\dfrac{1-x}{3}\)
4/ \(\dfrac{x-3}{2}-\dfrac{x+1}{10}=\dfrac{x-2}{5}\)
5/ \(\dfrac{4x+1}{4}-\dfrac{9x-5}{12}+\dfrac{x-2}{3}=0\)
Giải các phương trình sau:
\(a.\dfrac{4x-5}{x-1}=2+\dfrac{x}{x-1}\)
\(b.\dfrac{7}{x+2}=\dfrac{3}{x-5}\)
\(c.\dfrac{14}{3x-12}-\dfrac{2+x}{x-4}=\dfrac{3}{8-2x}-\dfrac{5}{6}\)
\(d.\dfrac{x+1}{x-1}-\dfrac{x-1}{x+1}=\dfrac{16}{x^2-1}\)
Tìm số tự nhiên x thỏa mãn cả 2 BPT sau: 6 (1-x) + 4 (2-x) ≤ 3 ( 1-3x) và \(\dfrac{1-2x}{4}-2< \dfrac{-5x}{8}\)