Tìm x
5^2x-3-2.5^2=5^2x3
1. (x3 – 3x2 + x – 3) : (x – 3) 2. (2x4 – 5x2 + x3 – 3 – 3x) : (x2 – 3) 3. (x – y – z)5 : (x – y – z)3 4. (x2 + 2x + x2 – 4) : (x + 2) 5. (2x3 + 5x2 – 2x + 3) : (2x2 – x + 1) 6. (2x3 – 5x2 + 6x – 15) : (2x – 5)
1: \(=x^2+1\)
3: \(=\left(x-y-z\right)^2\)
1) Rút gọn C = ( 3x- 5) ( 2x + 11 ) - (2x + 3) ( 3x + 7)
2) Thực hiện phép tính ( 2x4+ 2x3 - 7x2 -x +3) : ( 2x2 - 1)
3) Tìm x : ( x+ 4) ( x2 - 4x + 16) - x ( x- 5) (x+ 5) = 264
Bài 3:
\(\Leftrightarrow x^3+64-x^3+25x=264\)
hay x=8
\(1,C=6x^2+23x-55-6x^2-23x-21=-76\\ 2,=\left(2x^4-x^2+2x^3-x-6x^2+6-3\right):\left(2x^2-1\right)\\ =\left[\left(2x^2-1\right)\left(x^2+x-6\right)-3\right]:\left(2x^2-1\right)\\ =x^2+x-6\left(dư.-3\right)\\ 3,\Leftrightarrow x^3+64-x^3+25x=264\\ \Leftrightarrow25x=200\Leftrightarrow x=8\)
52x-3-2.52=52.3. Tìm x
Tìm x
52x-3-2.52=52.3
\(\Leftrightarrow5^{2x}:5^3=5^2.3+2.5^2\)
\(\Leftrightarrow5^{2x}.5^3=5^2.5\)
\(\Leftrightarrow5^{2x}=5^2.5.5^3\)
\(\Leftrightarrow5^{2x}=5^6\Rightarrow2x=6\Rightarrow x=3\)
Tìm x
52x-3-2.52=52.3
52x-3 - 2.52 = 52.3
52x-3 = 52.3 + 2.52
52x-3 = 52.(3 + 2)
52x-3 = 52.5 = 53
=> 2x - 3 = 3
=> 2x = 3 + 3
=> 2x = 6
=> x = 6 : 2
=> x = 3
Vậy x = 3
52x-3-2.52=52.3
52x-3-50=75
52x-3=125
52x-3 = 53
2x-3=3
2x=6
x=3
\(5^{2x-3}-2.5^2=5^2.3\)
\(=>5^{2x-3}=5^2.3+2.5^2\)
\(=>5^{2x-3}=5^2.5\)đặt nhân tử chung nha
\(=>5^{2x-3}=5^3\)
\(=>2x-3=3\)
\(=>2x=3+3\)
\(=>2x=6\)
\(=>x=3\)
T nha các bạn thên mến
tìm x
52x-3-2.52=52.3
\(5^{2x-3}-2.5^2=5^2.3\)
\(5^{2x-3}-50=75\)
=>\(5^{2x-3}=75+50=125\)
Mà \(5^{2x-3}=125=5^3\)
=>2x-3=3
2x=3+3=6
=>x=3
-52x-32.52=52.3
\(5^{2x-3}\)-50=75
\(5^{2x-3}\)=75+50
\(5^{2x-3}\)=215
\(5^{2x-3}\) =\(5^3\)
\(\Rightarrow\) \(2x-3=3\)
\(2x=3+3\)
\(2x=6\)
\(x=6:2\)
\(x=3\)
Vậy x = 3
a) 5^x =125
b) 3^x = 81
c) 5^2x-3 - 2.5^2 = 5^2 . 3
Đề bài : Tìm x
a) 5x = 125
53 = 125
Vậy x = 3
b) 3x = 81
34 = 81
Vậy x = 4
c)52x-3 - 2 . 52 = 52 . 3
52x-3 = 52 . 3 + 2. 52
52x-3 = 52 . ( 3 + 2 )
52x-3 = 52 . 5
52x-3 = 53
=> 2x - 3 = 3
2x = 6
x = 3
Vậy x = 3
Tìm x:
52x - 3 - 2.52 = 52.3
\(5^{2x-3}-2.5^2=5^2.3\)
\(5^{2x}:5^3=5^2.3+2.5^2\)
\(5^{2x}:5^3=5^2.\left(3+2\right)\)
\(5^{2x}:5^3=5^3\)
\(5^{2x}=5^3.5^3\)
\(5^{2x}=5^6\)
\(\Rightarrow2x=6\)
\(\Rightarrow x=3\)
Bài1:Làm tính nhân:
a) 2x. (x2– 7x -3) b) ( -2x3+ y2-7xy). 4xy2 c)(-5x3).(2x2+3x-5)
d)(x2-2x+3). (x-4) e) ( 2x3-3x -1). (5x+2) g) 3(2x-1)-5(x-3)
\(a,=2x^3-14x^2-6x\\ b,=-8x^4y^2+4xy^4-28x^2y^3\\ c,=-10x^5-15x^4+25x^3\\ d,=x^3-4x^2-2x^2+8x+3x-12=x^3-6x^2+11x-12\\ e,=10x^4+4x^3-15x^2-6x-5x-2=10x^4+4x^3-15x^2-11x-2\\ g,=6x-3-5x+15=x+12\)