giải phương trình (5x-4)^4+(2-x)^4=17
Giải phương trình : 17 - 14(x + 1) = 13 - 4(x + 1) - 5(x - 3) Giải phương trình : 5x + 3,5 + (3x - 4) = 7x - 3(x - 0,5)
Ta có : 17 - 14(x + 1) = 13 - 4(x + 1) - 5(x - 3)
<=> 17 - 14x - 14 = 13 - 4x - 4 - 5x + 15
<=> -14x + 3 = -9x + 24
<=> -14x + 9x = 24 - 3
<=> -5x = 21
=> x = -4,2
Ta có : 5x + 3,5 + (3x - 4) = 7x - 3(x - 0,5)
<=> 5x + 3,5 + 3x - 4 = 7x - 3x + 1,5
<=> 8x - 0,5 = 4x + 1,5
=> 8x - 4x = 1,5 + 0,5
=> 4x = 2
=> x = \(\frac{1}{2}\)
17-14(x+1)=13-4(x+1)-5(x-3)
Giải phương trình:
a) 21x + 7 = 15x + 35
b) |5x + 3| - 2x = x - 17
c) (5x + 2)(3x - 4) = 0
a) \(21x+7=15x+35\)
\(\Leftrightarrow21x-15x=35-7\)
\(\Leftrightarrow6x=28\)
\(\Leftrightarrow x=\frac{28}{6}\)
b)\(|5x+3|-2x=x-17\)
\(\Leftrightarrow|5x+3|=3x-17\)
\(\Leftrightarrow\orbr{\begin{cases}5x+3=3x-17\\5x+3=17-3x\end{cases}\Leftrightarrow\orbr{\begin{cases}2x=-20\\8x=14\end{cases}}}\Leftrightarrow\orbr{\begin{cases}x=-10\\x=\frac{4}{7}\end{cases}}\)
c) \(\left(5x+2\right)\left(3x-4\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}5x+2=0\\3x-4=0\end{cases}\Leftrightarrow\orbr{\begin{cases}5x=-2\\3x=4\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=-\frac{2}{5}\\x=\frac{4}{3}\end{cases}}}\)
a) \(21x+7=15x+35\)
\(\Leftrightarrow\)\(6x=28\)
\(\Leftrightarrow\)\(x=\frac{14}{3}\)
Vậy...
b) \(\left|5x+3\right|-2x=x-17\)
\(\Leftrightarrow\)\(\left|5x+3\right|=3x-17\)
Nếu \(x\ge-\frac{3}{5}\)thì pt trở thành:
\(5x+3=3x-17\)
\(\Leftrightarrow\)\(2x=-20\)
\(\Leftrightarrow\)\(x=-10\)(loại)
Nếu \(x< -\frac{3}{5}\)thì pt trở thành:
\(-5x-3=3x-17\)
\(\Leftrightarrow\)\(8x=14\)
\(\Leftrightarrow\) \(x=\frac{7}{4}\) (loại)
Vậy pt vô nghiệm
c) \(\left(5x+2\right)\left(3x-4\right)=0\)
\(\Leftrightarrow\)\(\orbr{\begin{cases}5x+2=0\\3x-4=0\end{cases}}\)
\(\Leftrightarrow\)\(\orbr{\begin{cases}x=-\frac{2}{5}\\x=\frac{4}{3}\end{cases}}\)
Vậy...
a) \(\Leftrightarrow\)21x-15x=35-7 \(\Leftrightarrow\)6x=28 \(\Leftrightarrow\)x=28:6 \(\Leftrightarrow\)x=28/6
c)\(\Leftrightarrow\)\(\orbr{\begin{cases}5\text{x}+2=0\\3\text{x}-4=0\end{cases}}\Leftrightarrow\) \(\orbr{\begin{cases}5\text{x}=-2\\3\text{x}=4\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=-\frac{2}{5}\\x=\frac{4}{3}\end{cases}}\)
b) ko biết làm
Giải phương trình:
(5x+1)/(x^2+5) + (5x+2)/(x^2+4) + (5x+3)/(x^2+3) + (5x+4)/(x^2+2) = -4
Giải phương trình:
(5x+1)/(x^2+5) + (5x+2)/(x^2+4) + (5x+3)/(x^2+3) + (5x+4)/(x^2+2) = -4
giải phương trình :
a,\(\sqrt{5x^2+14x+9}-5\sqrt{x+1}=\sqrt{x^2-x-2}\)
b, \(x^2-8x+17=3\sqrt{x^3-7x+6}\)
c, \(x^2+5x+2=4\sqrt{x^3+3x^2+x-1}\)
1) Giải các phương trình sau:
a) 5(2x-3)-4(5x-7)=19-2(x+11)
b) 4(x+3)-7x+17=8(5x-1)+166
c) 17-14(x+1)=13-4(x+1)-5(x-3)
d) 5x+3,5+(3x-4)=7x-3(x-0,5)
e) 7(4x+3)-4(x-1)=15(x+0,75)+7
f) 3x+2,42+o,8x=3,38-0,2x
\(\text{a) 5(2x-3)-4(5x-7)=19-2(x+11)}\)
\(10x-15-20x+28=19-2x-22\)
\(10x-20x+2x=19-22-28+15\)
\(-8x=-16\)
\(\Rightarrow x=2\)
\(\text{b) 4(x+3)-7x+17=8(5x-1)+166}\)
\(4x+12-7x+17=40x-8+166\)
\(4x-7x-40x=-8+166-17-12\)
\(-43x=129\)
\(x=-3\)
\(\text{c) 17-14(x+1)=13-4(x+1)-5(x-3)}\)
\(17-14x+14=13-4x-4-5x+15\)
\(-14x+4x+5x=13-4+15-14-17\)
\(-5x=-7\)
\(x=\frac{7}{5}\)
\(\text{d) 5x+3,5+(3x-4)=7x-3(x-0,5)}\)
\(5x+3,5+3x-4=7x-3x+1,5\)
\(5x+3x-7x+3x=1,5-3,5\)
\(x=-2\)
\(\text{e) 7(4x+3)-4(x-1)=15(x+0,75)+7}\)
\(28x+21-4x+4=15x+11,25+7\)
\(28x-4x-15x=11,25+7-4-21\)
\(9x=\frac{-27}{4}\)
\(x=\frac{-3}{4}\)
\(\text{f) 3x+2,42+o,8x=3,38-0,2x}\)
\(3x+0,8x+0,2x=3,38-2,42\)
\(4x=\frac{24}{25}\)
\(x=\frac{6}{25}\)
chúc bạn học tốt !!
Giải phương trình sau :
a,\(\dfrac{7-3x}{12}+\dfrac{5x+2}{7}=x+13\)
b,\(\dfrac{3\left(x+3\right)}{4}-\dfrac{1}{2}=\dfrac{5x+9}{7}-\dfrac{7x-9}{4}\)
c,\(\dfrac{2x+1}{3}-\dfrac{5x+2}{7}=x+3\)
d,\(\dfrac{2x-3}{3}-\dfrac{2x+3}{7}=\dfrac{4x+3}{5}-17\)
a: \(\Leftrightarrow7\left(7-3x\right)+12\left(5x+2\right)=84\left(x+13\right)\)
\(\Leftrightarrow49-21x+60x+24=84x+1092\)
\(\Leftrightarrow39x-84x=1092-73\)
=>-45x=1019
hay x=-1019/45
b: \(\Leftrightarrow21\left(x+3\right)-14=4\left(5x+9\right)-7\left(7x-9\right)\)
=>21x+63-14=20x+36-49x+63
=>21x+49=-29x+99
=>50x=50
hay x=1
c: \(\Leftrightarrow7\left(2x+1\right)-3\left(5x+2\right)=21x+63\)
=>14x+7-15x-6-21x-63=0
=>-22x-64=0
hay x=-32/11
d: \(\Leftrightarrow35\left(2x-3\right)-15\left(2x+3\right)=21\left(4x+3\right)-17\cdot105\)
=>70x-105-30x-45=84x+63-1785
=>40x-150-84x+1722=0
=>-44x+1572=0
hay x=393/11
a, msc 12.7=84
Chuyển vế về =0 rồi làm
b,msc 28
c,làm tương tự
a, \(\Rightarrow49-21x+60x+24=84x+1092\)
\(\Leftrightarrow-45x=1019\Leftrightarrow x=-\dfrac{1019}{45}\)
b, \(\Rightarrow21\left(x+3\right)-14=4\left(5x+9\right)-7\left(7x-9\right)\)
\(\Leftrightarrow21x+63-14=20x+36-49x+63\)
\(\Leftrightarrow50x=50\Leftrightarrow x=1\)
c, \(\Rightarrow14x+7-15x-6=21x+63\Leftrightarrow-22x=62\Leftrightarrow x=-\dfrac{31}{11}\)
d, \(\Rightarrow35\left(2x-3\right)-15\left(2x+3\right)=21\left(4x+3\right)-105.17\)
\(\Leftrightarrow70x-105-30x-45=84x+63-1785\)
\(\Leftrightarrow-44x=-1572\Leftrightarrow x=\dfrac{393}{11}\)
giải phương trình :
1) -2(x - 3) + 5x (x - 1) = 5x (x + 1)
2) 7 - (2x + 4) = -(x + 4)
1) -2(x - 3) + 5x (x - 1) = 5x (x + 1)
<=> -2x + 6 + 5x2 - 5x = 5x2 + 5x
<=> 6 = 5x2 + 5x + 2x - 5x2 + 5x
<=> 6 = 12x
<=> \(\dfrac{6}{12}\) = x = 0,5
vậy tập nghiệm S ={0,5}
2) 7 - (2x + 4) = -(x + 4)
<=> 7 - 2x - 4 = -x - 4
<=> 7 - 4 + 4 = -x + 2x
<=> 7 = x
vậy tập nghiệm S ={7}
Giải phương trình: x/x^2+4x+4 +5x/x^2+4=-2