A. x^2x - 3 - 2×5^2= 5^2×3
B. 5^x +1 = 125
C . ( 12x _ 4 ^3 ) × 8^3 = 4 × 8 ^4
D. X ^50 = x
bài 2 viết mỗi tích, thương sau dưới dạng luỹ thừa
a) 4^10 x 2^30 b) 9^25 x 27^4 x 81^3 c) 25^50 x 125^5 d) 64^3 x 4^8 x 16^4
e)3^8:3^6 ; 2^10:8^3 ; 12^7 :6^7 ; 31^5 ; 81^3
f) 5^8 : 25^2 ; 4^9:64^2 ; 2^25 : 32^4 ; 125^3 : 25^4
a, 410. 230=220.230=250
b,925.274.813= 350.312.312=374
Tương tự các câu khác....
a, 410.230 = (22)10.230 = 220.230 = 250
b, 925.274.813 = (32)25.(33)4.(34)3 = 350.312.312 = 374
c, 2550.1255 = (52)50.(53)5 = 5100.515 = 5115
d, 643.48.164 = (26)3.(22)8.(24)4 = 218.216.216 = 250
e, 38 : 36 = 32
210 : 83 = 210 : (23)3 = 210 : 29 = 2
127 : 67 = (12 : 6)7 = 27
@Dương Tuyết Mai
a,5(3-2x)+5(x-4)=6-4x
b-5(2-x)+4(x-3)=10x-15
C,2(4x-8)-7(x-3)=|-4|(3-2)
d,8(x-|-7|)-6(x-2)=|-8|.6-50
\(a)5\left(3-2x\right)+5\left(x-4\right)=6-4x\)
\(\Leftrightarrow5\left(3-2x+x-4\right)=6-4x\)
\(\Leftrightarrow5\left(-x-1\right)=6-4x\)
\(\Leftrightarrow-5x-5=6-4x\)
\(\Leftrightarrow-x=11\Leftrightarrow x=-11\)
Vậy \(x=-11\)
\(b)-5\left(2-x\right)+4\left(x-3\right)=10x-15\)
\(\Leftrightarrow-10+5x+4x-12=10x-15\)
\(\Leftrightarrow-22+9x=10x-15\)
\(\Leftrightarrow-x=7\Leftrightarrow x=-7\)
Vậy \(x=-7\)
a). (x^4+4x^3+5+8)÷(2x+5)
b). (5x^3+14x^2+12x+8)÷(x+2)
c). (4x^2-4x+1)÷(2x-1)
d). (2x^3+5x^2+6x+15)÷(2x+5)
bài 1:
a)7x(x2-7x+3) b)(x+6)(x-7)
c)(x-8)2 d) (3x+2)2
e)(x-4)(x+4)-(5-x)2
Bài 2:
a)2(x-7)-9=10 b)(2x-5)2-x(4x-3)=2x+50
\(1,\\ a,=7x^3-49x^2+21x\\ b,=x^2-x-42\\ c,=x^2-16x+64\\ d,=9x^2+12x+4\\ e,=x^2-16-25+10x-x^2=10x-41\\ 2,\\ a,\Rightarrow2\left(x-7\right)=19\\ \Rightarrow x-7=\dfrac{19}{2}\Rightarrow x=\dfrac{33}{2}\\ b,\Rightarrow4x^2-20x+25-4x^2+3x-2x=50\\ \Rightarrow-19x=25\Rightarrow x=-\dfrac{25}{19}\)
Bài 1 :Tính nhanh giá trị biểu thức
a) 4 . 415 . 8 . 25 . 125
b) 2 . 31 . 12 + 4 . 42 . 6 + 8 . 27 . 3
Bài 2 : Tìm số tự nhiên x
a ) 4 mũ 2x - 3 + 7 . 4 mũ 3 = 4 mũ 3 . 23
b) 3600 : [ ( 5x + 335) : x ] = 50
c ) 5026 + 8x = 6x +
d) 25 mũ x = 4A + 5 với A = 5 + 5 mũ 2 + 5 mũ 3 + ..........+ 5 mũ 2016 + 5 mũ 2017
1. a) 4.415.8.25.125
= (4.25). (8.125).415
= 100.1000.415
= 100000.415
= 41500000
b) 2.31.12+4.42.6+8.27.3
= (2.31.12)+(4.42.6)+(8.27.3)
= (2.12).31+(4.6).42+(8.3).27
= 24.31+24.42+24.27
= 24 (31+42+27)
= 24.100
= 2400
1timf x biết
a/52x-3-2.52 =52.3
b/128-3(x+4)=23
c/[(12X-43).8X=4.84
d/390-(x-7)=169/13
e/(x-6)2=9
g/5x+1=125
h/(x-5)4=(x-5)6
Tìm x
a,64.4^x=16^8
b,(2x+1)^3=125
c,(x-5)^4=(x-5)^6
d,(x-1)^x+2=(x-1)^x+4
e,1+3+5+...+99=(x-2)^2
g,1^3+2^3+3^3+...+10^3=(x+1)^2
a) 64 * 4^x = 16^8
4^x = 16^8 : 64
4^x = 2^32 : 2^6
4^x = 2^26
4^x = (2^2)13
4^x = 4^13
=> x= 13
b) (2x+1)^3 = 5^3
=> 2x+1 = 5
2x = 4
x= 2
c) (x-5)^4 =(x-5)^6
d) (x-1)^x+2 = (x-1)^x+4
(x-1)^x * (x-1)^2 = (x-1)^x * (x-1)^4
(x-1)^x = (x-1)^4 :(x-2)^2
(x-1)^x = (x-2)^2
=> x=2
bạn giúp mình giải luôn bài 1 tính đc hông zợ ???
bài 1 : tìm x biết ;
a) 2x + 3 = 5 b)(2x - 3)2= 9 c)3x + 4 = 2x - 7 d)(4x - 1)3= 27 e) (x - 7) . 2 =3(2x +4) f) 52x-1= 125 g) 3.(x + 6) - 2x = 3 + 12x
Nếu bài dễ thì cố gắng tự làm bạn nhé.
Bài 1:
a) \(2x+3=5\)
\(\Leftrightarrow2x=5-3=2\)
\(\Leftrightarrow x=2:2=1\)
Vậy: x=1
b) \(\left(2x-3\right)^2=9\)\(=3^2=\left(-3\right)^2\)
\(\Rightarrow\left[{}\begin{matrix}2x-3=3\\2x-3=-3\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\left(3+3\right):2=3\\x=\left(-3+3\right):2=0\end{matrix}\right.\)
Vậy: \(x\in\left\{3;0\right\}\)
c) \(3x+4=2x-7\)
\(\Leftrightarrow2x-3x=7+4\)
\(\Leftrightarrow-1x=11\)
\(\Leftrightarrow x=-11\)
Vậy: x=-11
d) \(\left(4x-1\right)^3=27\)\(=3^3\)
\(\Rightarrow4x-1=3\)
\(\Leftrightarrow4x=3+1=4\)
\(\Leftrightarrow x=4:4=1\)
Vậy: x=1
e) \(\left(x-7\right).2=3.\left(2x+4\right)\)
\(\Leftrightarrow2x-14=6x+12\)
\(\Leftrightarrow2x-6x=12+14\)
\(\Leftrightarrow-4x=26\)
\(\Leftrightarrow x=\frac{26}{-4}=\frac{13}{-2}\)
Vậy: \(x=\frac{13}{-2}\)
Bài 2. Tìm x biết:
a, 128 - 3(x + 4) = 23 d, 720 : [41 - (2x - 5)] = 2 3 .5
b, [(4x + 28).3 + 55] : 5 = 35 e, 123 – 5.( x + 4 ) = 38
c, (12x - 4 3 ).8 3 = 4.8 4 g, ( 3x – 2 4 ) .7 3 = 2.7 4
a,
128-3x-12=23
3x=128-12-23
3x=93
x=93:3
= 31
b,
(12x+84+55):5=35
12x+84+55=35.5
12x+84+55=175
12x=175-55-84
12x=36
x=36:12
x=3