(5x+2)^3=-625
Những câu hỏi liên quan
<5x-10>^3=625^3:125
5x.(5^3)^2=625
(12/25)^x=(3/5)^2+(3/5)^4
27<813 : 8x<243
a) |x-1|-2x=5
b)|9-7x|=5x-3
c)5x+2=625
d)(2x-3)2=36
a) |x-1|-2x=5
b)|9-7x|=5x-3
c)5x+2=625
d)(2x-3)2=36
a) |x-1|-2x=5
\(\Leftrightarrow\) x - 1 - 2x = 5 (đk: x\(\ge\)1 ) (1)
hoặc -x + 1 - 2x = 5 ( đk: x < 1) (2)
(1): \(\Leftrightarrow\) x - 2x = 5 + 1
\(\Leftrightarrow\) - x = 6
\(\Leftrightarrow\) x = -6 (ko thỏa mãn)
(2): \(\Leftrightarrow\) -x + 1 - 2x = 5
\(\Leftrightarrow\) -3x = 4
\(\Leftrightarrow\) x = \(\frac{-4}{3}\) (thỏa mãn)
Vậy: x = \(\frac{-4}{3}\)
b) |9-7x|=5x-3
\(\Leftrightarrow\) 9 - 7x = 5x - 3 (đk: \(\le\) \(\frac{9}{7}\) ) (1)
hoặc -9 + 7x = 5x - 3 (đk: x > \(\frac{9}{7}\) ) (2)
(1): \(\Leftrightarrow\) -7x-5x = -3-9 \(\Leftrightarrow\) -12x = -12 \(\Leftrightarrow\) x = 1 ( thỏa mãn)
(2): \(\Leftrightarrow\) 7x - 5x = -3 + 9 \(\Leftrightarrow\) 2x = 6 \(\Leftrightarrow\) x = 3 ( thỏa mãn)
Vậy: x= 1; 3
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c) 5x+2 = 625
\(\Leftrightarrow\) 5x . 52 = 54
\(\Leftrightarrow\) 5x = \(\frac{5^4}{5^2}\)= 52
\(\Leftrightarrow\) x = 2
d) (2x - 3)2 = 36
\(\Leftrightarrow\) \(\left[{}\begin{matrix}2x-3=6\left(đk:x\ge\frac{3}{2}\right)\text{}\Leftrightarrow x=4,5\left(TMĐK\right)\\2x-3=-6\left(đk:x< \frac{3}{2}\right)\Leftrightarrow x=-1,5\left(TMĐK\right)\end{matrix}\right.\)
Vậy: x = 4,5; -1,5
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A, 6x^2 - 12xy + 6y^2
B, 36x^2 - y^2 +10x + 25
C, 101a^2 -50a + 625
D,20x^4 - 20x^3 y^3 + 5x^2 y^4
tìm x biết:
a/ 5x .(53)2 =625
b/ (5x+1)2 = 36/49
5x.(5^3)^2=625
(12/25)^x=(3/5)^2+(3/5)^4
27<813 : 8x<243
giúp mình nha huhu
2x-74:37=100
10+2.x=45:43
5x3=625
Tìm x bt:
a) 33x+1.5=10935
b) 25x+1.3=6144
c) (2x+3)4=625
d) (3x+1)3=343
a) 33x+1 . 5 = 10935
=> 33x . 3 . 5 = 10935
=> 27x . 3 . 5 = 10935
=> 27x = 729
=> 27x = 272
=> x = 2
b) 25x + 1 . 3 = 6144
=> 25x . 2 . 3 = 6144
=> 32x . 6 = 6144
=> 32x = 1024
=> 32x = 322
=> x = 2
c) (2x + 3)4 = 625
=> (2x + 3)4 = (\(\pm\)5)4
=> \(\orbr{\begin{cases}2x+3=5\\2x+3=-5\end{cases}}\Rightarrow\orbr{\begin{cases}x=1\\x=-4\end{cases}}\)
d) (3x + 1)3 = 343
=> (3x + 1)3 = 73
=> 3x + 1 = 7 => 3x = 6 => x = 2
a) 33x + 1. 5 = 10935
33x+1 = 10935 : 5
33x+1 = 2187
33x+1 = 37
=> 3x + 1 = 7
3x = 7 - 1
3x = 6
x = 6:3
=> x = 2
a) \(3^{3x+1}\cdot5=10935\)
\(\Leftrightarrow3^{3x+1}=2187=3^7\)
\(\Rightarrow3x+1=7\)
\(\Leftrightarrow3x=6\)
\(\Rightarrow x=2\)
b) \(2^{5x+1}\cdot3=6144\)
\(\Leftrightarrow2^{5x+1}=2048=2^{11}\)
\(\Leftrightarrow5x+1=11\)
\(\Leftrightarrow5x=10\)
\(\Rightarrow x=2\)
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