5^x-2 - 3^2=2^4 -(2^8.2^4-2^10.2^2)
giup minh voi cac ban :
1timx
5^x-2-3^2=2^4-(2^8.2^4-2^10.2^2)
697:[(15^x+364):x]=17
134:(x-3)=35+160:5
(3.x-2^4).7^3=2.7^4
[(10-x) .2+5]:3-2=3
2 tim x thuoc N
cau a : n+5chia het n +1
cau b :2.n +7 chia het cho n-2
Lúc bạn hỏi, bạn đang bằng tuổi tôi đấy. Còn giờ...
Tìm X biết:
X:4 1/3= -2,5
X: -3/5= -10/21
2/3 x-1/2=1/10
1/2x+1/2=5/2
-2/3-1/3(2x-5)=3/2
2/5.x+1/2=-3/4
1/3x-8=1/2
X-1/4=5/8.2/3
\(x\div4\frac{1}{3}=-2,5\)
\(\Leftrightarrow x\div\frac{13}{3}=\frac{-5}{2}\)
\(\Leftrightarrow x=\frac{-5}{2}.\frac{13}{3}\)
\(\Leftrightarrow x=\frac{-65}{6}\)
\(x\div\frac{-3}{5}=\frac{-10}{21}\)
\(\Leftrightarrow x=\frac{-10}{21}.\frac{-3}{5}\)
\(\Leftrightarrow x=\frac{30}{105}\)
\(\Leftrightarrow x=\frac{2}{7}\)
\(\frac{2}{3}x-\frac{1}{2}=\frac{1}{10}\)
\(\Leftrightarrow\frac{2}{3}x=\frac{1}{10}+\frac{1}{2}\)
\(\Leftrightarrow\frac{2}{3}x=\frac{6}{10}\)
\(\Leftrightarrow x=\frac{6}{10}\div\frac{2}{3}\)
\(\Leftrightarrow x=\frac{18}{20}\)
\(\Leftrightarrow x=\frac{9}{10}\)
\(\frac{1}{2}x+\frac{1}{2}=\frac{5}{2}\)
\(\Leftrightarrow\frac{1}{2}\left(x+1\right)=\frac{5}{2}\)
\(\Leftrightarrow\left(x+1\right)=\frac{5}{2}\div\frac{1}{2}\)
\(\Leftrightarrow\left(x+1\right)=5\)
\(\Leftrightarrow x=5-1\)
\(\Leftrightarrow x=4\)
\(\frac{-2}{3}-\frac{1}{3}\left(2x-5\right)=\frac{3}{2}\)
\(\Leftrightarrow\frac{-2}{3}-\frac{2x}{3}+\frac{5}{3}=\frac{3}{2}\)
\(\Leftrightarrow1-\frac{2x}{3}=\frac{3}{2}\)
\(\Leftrightarrow\frac{2x}{3}=1-\frac{3}{2}\)
\(\Leftrightarrow\frac{2x}{3}=\frac{-1}{2}\)
\(\Leftrightarrow x=\frac{-1}{2}\div\frac{2}{3}\)
\(\Leftrightarrow x=\frac{-3}{4}\)
\(\frac{2}{5}x+\frac{1}{2}=\frac{-3}{4}\)
\(\Leftrightarrow\frac{2}{5}x=\frac{-3}{4}-\frac{1}{2}\)
\(\Leftrightarrow\frac{2}{5}x=\frac{-5}{4}\)
\(\Leftrightarrow x=\frac{-5}{4}\div\frac{2}{5}\)
\(\Leftrightarrow x=\frac{-25}{8}\)
tìm x:
a) \(5^{x-2}-3^2=2^4-\left(2^8.2^4-2^{10}.2^2\right)\)
b) 697 : [ ( 15x + 364 ) : x ] = 17
c)\(\left(3x-2^4\right).7^3=2.7^4\)
tìm x:
\(^{5^{x-2}-3^2=2^4-\left(2^8.2^4-2^{10}.2^2\right)}\)
\(697:\left[\left(15x+364\right):x\right]=17\)
\(\left(3x-2^4\right).7^3=2.7^4\)
1. [(-x)^3]^4 2.(-1/2)^8.2^3
\(\left[\left(-x\right)^3\right]^4=\left(-x\right)^{12}\)
\(\left(\dfrac{-1}{2}\right)^8\times2^3=\dfrac{1}{256}\times8=\dfrac{1}{32}\)
1) \(\left[\left(-x\right)^3\right]^4=\left(-x\right)^{12}=x^{12}\)
2) \(\left(-\dfrac{1}{2}\right)^8\cdot2^3=\dfrac{1}{256}\cdot8=\dfrac{1}{32}\)
Bài 1 : Phân tích các đa thức sau thành nhân tử bằng phương pháp dùng hằng đẳng thức :
a ) x^2-3
b) (a+b)^2-(a+b)^2
c) x^3-27b^3
Bài 2 : Phân tích các đa thức sau thành nhân tử bằng phương pháp nhóm các hạng tử :
1) a^2+2ab+b^2-c^2
2) x^2-y^2-4x+4
3) x^3-4x^2-8x+8
4) x^3-x
5) 5x^3-10x^2+5x
Bài 3 : Tính Nhanh :
a) 99^3+1+3*(99^2+99)
b) 10.2*9.8-9.8*0.2+10.2^2-10.2*0.2
c) 892^2+892*216+108^2
bài 1: a) \(x^2-3=x^2-\left(\sqrt{3}\right)^2=\left(x+\sqrt{3}\right)\left(x-\sqrt{3}\right)\)
b) \(\left(a+b\right)^2-\left(a+b\right)^2=\left(a+b+a+b\right)\left(a+b-a-b\right)=2a+2b=2\left(a+b\right)\)
c) \(x^3-27b^3=\left(x-3b\right)\left(x^2+3xb+b^2\right)\)
giúp mik nha
4.10-x:2=1
5.x:4+3*2=7
6.2:x+5=6
7.2*x*3*5=30
8.2*x:10*2=1
9.18:x-5*2=8
10.5*5-2:x=24
a) 10 - x : 2 = 1
x: 2 = 9
x = 18
b) x:4 + 3 x 2 = 7
x:4 + 6 = 7
x:4 = 1
x = 4
c) 2: x + 5 = 6
2: x = 1
x = 2
+4.10-x:2=1
40-x:2=1
x:2=40-1
x:2=39
x:2=19,5
+5.x:4+3*2=7
5.x:4+6=7
5.x:4=7-6=1
5.x=1.4=4
x=4:5
x=0,8
+6.2:x+5=6
12:x=6-5
12:x=1
x=12:1
x=12
+7.2*x*3*5=30
14.x.15=30
14.x=2
x=2:14
x=1/7
+8.2*x:10*2=1
16.x:20=1
16.x=20
x=20:16
x=1,25
9.18:x-5*2=8
10.5*5-2:x=24
d) 2 * x * 3 * 5 = 30
x * 30 = 30
x = 1
e) 2 * x : 10* 2 = 1
2*x * 1/10 * 2 = 1
2/5 * x = 1
x = 5/2
g) 18 : x - 5*2 = 8
18 : x - 10 = 8
18 : x = 18
x = 1
h) 5*5 -2 : x = 24
25 - 2:x = 24
2:x = 1
x = 2
Viết tích sau dưới dạng một lũy thừa:
x.x2.x3.x4.x5.............x49.x50
22x: 22=10.24+6.24
x.x2.x3.x4.x5.............x49.x50
=x1+2+3+...+50
=x5050
x.x2.x3.x4.x5.............x49.x50
=1+2+3+4+.......+49+50
=[(50-1)+1]. (50+1):2
=[49+1].51:2
=50.51:2
=50:2.51
=25.51
=1275
giải phương trình:
a, \(\sqrt{25x+75}+3\sqrt{x-2}=2+4\sqrt{x+3}+\sqrt{9x-18}\)
b, 4x-10.2x+16=0
c, x(x-1)(x+4)(x+5)=84
a: \(\Leftrightarrow5\sqrt{x+3}-4\sqrt{x+3}=3\sqrt{x-2}-3\sqrt{x-2}+2\)
\(\Leftrightarrow\sqrt{x+3}=2\)
=>x+3=4
hay x=1
c: \(\Leftrightarrow\left(x^2+4x\right)\left(x^2+4x-5\right)=84\)
\(\Leftrightarrow\left(x^2+4x\right)^2-5\left(x^2+4x\right)-84=0\)
\(\Leftrightarrow\left(x^2+4x\right)^2-12\left(x^2+4x\right)+7\left(x^2+4x\right)-84=0\)
\(\Leftrightarrow x^2+4x-12=0\)
=>(x+6)(x-2)=0
=>x=-6 hoặc x=2