a)
\(5x\left(4-8x\right)+40\left(x^2-1\right)=3\\ \Leftrightarrow20x-40x^2+40x^2-40=3\\ \Leftrightarrow20x-40=3\\ \Leftrightarrow20\left(x-2\right)=3\\ \Leftrightarrow x-2=\frac{3}{20}\\ \Leftrightarrow x=\frac{43}{20}\)
b)
\(\left(4x-5\right)\left(7-8x\right)+4x\left(3+8x\right)=4\\ \Leftrightarrow28x-32x^2-35+40x+12x+32x^2=4\\ \Leftrightarrow80x-35=4\\ \Leftrightarrow80x=39\\ \Leftrightarrow x=\frac{39}{80}\)
a) \(5x\left(4-8x\right)+40\left(x^2-1\right)=3\)
\(\Leftrightarrow\)\(20x-40x^2+40x^2-40=3\)
\(\Leftrightarrow20x-40=3\)
\(\Leftrightarrow20x=43\)
\(\Leftrightarrow x=\frac{43}{20}\)
b, \(\left(4x-5\right)\left(7-8x\right)+4x\left(3+8x\right)=4\)
\(\Leftrightarrow28x-32x^2-35+40x+12x+32x^2=4\)
\(\Leftrightarrow80x-35=4\)
\(\Leftrightarrow80x=39\)
\(\Leftrightarrow x=\frac{39}{80}\)
a) 5x (4-8x) + 40 (x^2 -1) = 3
20x - 40x^2 + 40x^2 - 40 = 3
20x -40 = 3
20x = 43
x = \(\frac{43}{\frac{20}{ }}\)
Vậy x = \(\frac{43}{20}\)
b) (4x-5) ( 7-8x) + 4x (3+8x) =4
28x-32x^2-35+40x + 12x + 32x^2 = 4
80x - 35 = 4
80x = 39
x= \(\frac{39}{80}\)
Vậy x = \(\frac{39}{80}\)
Xin lỗi vì mk ko bt cách gõ mũ, nếu sai thì cho mk thứ lỗi (vì mk ko có máy tính bỏ túi nên tính bằng đầu).
