12.(x-3):3+4mu3+2mu3
hãy viết thành một bình phương
1mu3+2mu3+3mu3+4mu3+5mu3
1mu3+2mu3+3mu3+4mu3+5mu3+6mu3
tìm x biết:
a,12 x 4 + 225 : (x - 3)mu2=37
b,2 nhân x - 138=2mu3 nhan 3mu2
a) \(12.4+225:\left(x-3\right)^2=37\)
\(48+225:\left(x^2-6x+9\right)=37\)
\(48+\frac{225}{x^2}-\frac{225}{6x}+\frac{225}{9}=37\)
\(48+\frac{15}{x}-\frac{37,5}{x}+25=37\)
\(48-\frac{22,5}{x}+25=37\)
\(\frac{-22,5}{x}=37-25-48\)
\(\frac{-22,5}{x}=-36\)
\(x=-22,5:-36\)
\(x=\frac{5}{8}\)
vậy \(x=\frac{5}{8}\)
b) \(2x-138=2^3.3^2\)
\(2x-138=72\)
\(2x=72+138\)
\(2x=210\)
\(x=105\)
vậy \(x=105\)
b,2 nhân x - 138 =72
2 nhân x =72 + 138
2 nhân x =210
x =210 : 2
x =105
46-6.(x-3)=2mu3 . 5
\(46-6\left(x-3\right)=2^3.5\)
\(\Rightarrow46-6\left(x-3\right)=40\)
\(\Rightarrow6\left(x-3\right)=6\)
\(\Rightarrow x-3=1\Rightarrow x=4\)
4mu x.4mu3=256 tìm x
\(\Rightarrow4^x=4^4:4^3=4^1\\ \Rightarrow x=1\)
1.tính
5871:[928-(247-82.5)]
2,tìm x bít
a)128-3.(x+4)=22
b)(12x-4mu3).8mu3=4.8mu4
\(5871:\left[928-\left(247-82.5\right)\right]\)
\(=5871:\left[928-\left(247-460\right)\right]\)
\(=5871:\left[928-\left(-213\right)\right]\)
\(=5871:1141\)
a)
26-3(X+1)=17b)
5X-8=2mu3*2mu2
a) 26- 3(X+1) = 17
3(X+1) = 26 - 17
3(X+1) = 9
X+1 = 9: 3
X+1 = 3
X = 3- 1
Vậy:X =2
b) 5X -8 = 23. 22
5X - 8 = 8 . 4
5X - 8 = 32
5X =32+8
5X = 40
X = 40 :5
Vậy X = 8
Trung Thu vui vẻ nha mn
4 mu x = 4mu3 × 4mu5
2mux = 8× 128
\(4^x=4^3.4^5\Rightarrow x=3+5=8\)
\(2^x=8.128\Rightarrow2^x=2^3.2^7\Rightarrow x=3+7=10\)
\(4^X=4^3.4^5\)
\(4^X\)=\(4^7\)
\(\Rightarrow\)X=7
\(2^X=8.128\)
\(2^X=2^3.2^7\)
\(2^X\)=\(2^{10}\)
\(\Rightarrow\)x=10
chú ý: dấu nhân kí hiệu là .
4x=43.45
4x=43+5
4x=48
<=> x=8
2x=8.128
2x=23.27
2x=23+7
2x=210
<=> x=10
Tinh
a} A=24x47-23\24+47- 23 x 3+3\7-3\11=3\1001-3\13 \ 9\1001-9\13+9\7-9\11+9
b} M=1+2 +2 mũ 2 +2mu3+....+2mu2012\2mu2014-2
#)Giải ;
b) Đặt \(N=1+2+2^2+2^3+...+2^{2012}\)
\(\Rightarrow2N=2+2^2+2^3+2^4+...+2^{2013}\)
\(\Rightarrow2N-N=N=\left(2+2^2+2^3+2^4+...+2^{2013}\right)-\left(1+2+2^2+2^3+...+2^{2012}\right)\)
\(\Rightarrow N=2^{2013}-1\)
Thay N vào M, ta có :
\(M=\frac{2^{2013}-1}{2^{2014}-2}\)
Thêm Cho pen
\(M=\frac{2^{2013}-1}{2^{2014}-2}=\frac{2^{2013}-1}{2.\left(2^{2013}-1\right)}=\frac{1}{2}\)
Phải tính hết nhé
a, \(A=\frac{24\cdot47-23}{24+47-23}\cdot\frac{3+\frac{3}{7}-\frac{3}{11}+\frac{3}{1001}-\frac{3}{13}}{\frac{9}{1001}-\frac{9}{13}+\frac{9}{7}-\frac{9}{11}+9}\)
\(A=\frac{24\cdot47-23}{24+47-23}\cdot\frac{3.\left(1+\frac{1}{7}-\frac{1}{11}+\frac{1}{1001}-\frac{1}{13}\right)}{9.\left(1+\frac{1}{7}-\frac{1}{11}+\frac{1}{1001}-\frac{1}{13}\right)}\)
\(A=\frac{24\cdot47-23}{24+47-23}\cdot\frac{3}{9}\)
\(A=\frac{1105}{48}\cdot\frac{1}{3}=\frac{1105}{144}\)
Vậy A = \(\frac{1105}{144}\)
b, Đặt A = 1 + 2 + 2^2 + 2^3 + ... + 2^2012
2A = 2(1 + 2 + 2^2 + 2^3 + ... + 2^2012)
2A = 2 + 2^2 + 2^3 + 2^4 + ... + 2^2012
2A - A = (2 + 2^2 + 2^3 + 2^4 + ... + 2^2012) - (1 + 2 + 2^2 + 2^3 + ... + 2^2012)
A = 2^2012 - 1
=> M = \(\frac{2^{2012}-1}{2^{2014}-2}=\frac{2^{2012}-1}{2^{2014}-2}=\frac{2^{2012}-1}{2.2.\left(2^{2012}-1\right).}=0,25\)
Vậy M = 0,25
cho bieu thuc A= 2+2mu2 + 2mu3 +.....+2mu40
chung to rang A chia het cho 3, 7
tinh tong A . tim so tu nhien x de A+2 = 2 mua x-1