Tính :
a) \(125.\left(-24\right)+24.225\)
b) \(26.\left(-125\right)-125.\left(-36\right)\)
Bài 1: Tính nhanh
A) \(\left(-356+57\right)-\left(27-356\right)\)
B) \(125.\left(-24+24.225\right)\)
C) 26. ( - 125) - 125 . (-36)
Bài 2:Tìm x \(\in\) Z, biết :
a) ( 2x - 4)2 = 0 ( Số 2 đằng sau số 4) là mũ 2)
b) ( x + 5) \(⋮\) ( x + 3 )
câu a bài 1 đáp án là -682
câu b đáp án là -675000
câu c đáp án là 112500
bài 2 tui suy nghĩ đã
Bài 1; Tính nhanh
a) \(\left(-356+57\right)-\left(27-356\right)\)
b) \(125.\left(-24+24.225\right)\)
c) 26. ( - 125) - 125 . (-36)
Bài 2:Tìm x \(\in\) Z, biết :
a) ( 2x - 4)2 = 0 ( 2 in đậm là mũ 2
b) ( x + 5) \(⋮\) ( x + 3 )
Bài 1:
\(a.\left(-356+57\right)-\left(27-356\right)=-356+57-27+356=\left(-356+356\right)+\left(57-27\right)=30\) \(b.125.\left(-24+24.225\right)=125.\left(-24+5400\right)=125.\left(-24\right)+125.5400=-3000+675000=672000\)
\(c.26.\left(-125\right)-125.\left(-36\right)=-125.\left(26-36\right)=-125.\left(-10\right)=1250\)
Bài 2:
\(a.\left(2x-4\right)^2=0\)
\(\Rightarrow2x-4=0\)
\(\Rightarrow2x=4\)
\(\Rightarrow x=2\)
\(b.\frac{x+5}{x+3}=\frac{x+3+2}{x+3}=\frac{x+3}{x+3}+\frac{2}{x+3}=1+\frac{2}{x+3}\)
Để (x+5) chia hết cho (x+3) thì 2 phải chia hết cho (x+3)
\(\Rightarrow x+3\inƯ\left(2\right)=\left\{\pm1;\pm2\right\}\)
\(x+3=1\Rightarrow x=-2\)
\(x+3=-1\Rightarrow x=-4\)
\(x+3=2\Rightarrow x=-1\)
\(x+3=-2\Rightarrow x=-5\)
Vậy \(x\in\left\{-2;-4;-1;-5\right\}\)
Bài 2:
a)\(\left(2x-4\right)^2=0\)
\(\Leftrightarrow2x-4=0\)
\(\Leftrightarrow2x=4\Leftrightarrow x=2\)
b)\(\frac{x+5}{x+3}=\frac{x+3+2}{x+3}=\frac{x+3}{x+3}+\frac{2}{x+3}=1+\frac{2}{x+3}\in Z\)
Suy ra \(2⋮x+3\Rightarrow x+3\inƯ\left(2\right)=\left\{1;-1;2;-2\right\}\)
\(\Rightarrow x\in\left\{-2;-4;-1;-5\right\}\)
Tính nhanh:
a) 125.(-24) + 24.225
b) 26.(-125) - 125.(-36)
a)125.(-24) + 24.225
= 125. [(-24) + 24].225
= 125.0.225
= 0.
1 Tính nhanh:
a, 125. (-24)+24.225
b, 26.(-125)-125.(-36)+125. (-7)
1. Tính nhanh:
a) \(125.\left(-24\right)+24.225\)
= \(-125.24+24.225\)
\(=24\left(-125+225\right)\)
\(=24\) . \(100\)
= \(2400\)
b) \(26.\left(-125\right)-125.\left(-36\right)+125.\left(-7\right)\)
\(=-26.125-125.\left(-36\right)+125.\left(-7\right)\)
\(=125\left[-26-\left(-36\right)+\left(-7\right)\right]\)
\(=125.3\)
\(=375.\)
a, \(125\cdot\left(-24\right)+24\cdot225\)
\(=\left(-125\right)\cdot24+24\cdot225\)
\(=24\cdot\left[\left(-125\right)+225\right]\)
\(=24\cdot100\)
\(=2400\)
b, \(26\cdot\left(-125\right)-125\cdot\left(-36\right)+125\cdot\left(-7\right)\)
\(=\left(-26\right)\cdot125-125\cdot\left(-36\right)+125\cdot\left(-7\right)\)
\(=125\cdot\left[\left(-26\right)+36-7\right]\)
\(=125\cdot3\)
\(=375\)
a) 125. (-24)+24.225
b)26.(-125)-125.(-36)
Các bạn tính hộ mình nhé <3 Cám ơn ạ
a)-125.24+24.225
=24.(-125+225)
=24.100
=2400
b)-26.125-125.(-36)
=125.(-26+36)
=125.10
=1250
a, 2400
b,1250
k mk nhé chi nguyễn mk kv vs bn rồi
a, 125.(-24)+24.225
=-125.24+24.225
=24.(-125+225)
=24.100
=2400
b, 26.(-125)-125.(-36)
=-26.125-125.(-36)
=125.(-26+36)
=125.10
=1250
Tính giá trị của biểu thức \(A=\left(\frac{1}{125}-\frac{1}{1^3}\right).\left(\frac{1}{125}-\frac{1}{2^3}\right).\left(\frac{1}{125}-\frac{1}{3^3}\right)...\left(\frac{1}{125}-\frac{1}{19^3}\right).\left(\frac{1}{125}-\frac{1}{20^3}\right)\)
Tính nhanh : A= \(\left(\frac{1}{125}-\frac{1}{1^3}\right)\cdot\left(\frac{1}{125}-\frac{1}{2^3}\right)\cdot\left(\frac{1}{125}-\frac{1}{3^3}\right).....\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
\(=\)\(\left(\frac{1}{125}-\frac{1}{1^3}\right)\) \(.\) \(\left(\frac{1}{125}-\frac{1}{2^3}\right)\) \(.\) \(\left(\frac{1}{125}-\frac{1}{3^3}\right)\) \(.\) \(\left(\frac{1}{125}-\frac{1}{5^3}\right)\)\(...\) \(\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
\(=\) \(\left(\frac{1}{125}-\frac{1}{1^3}\right)\) \(.\) \(\left(\frac{1}{125}-\frac{1}{2^3}\right)\) \(.\) \(\left(\frac{1}{125}-\frac{1}{3^3}\right)\) \(.\) \(0\) \(....\) \(\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
\(=\) \(0\)
A)\(2009^{\left(1000-1^3\right)\cdot\left(1000-2^3\right)\cdot...\cdot\left(1000-15^3\right)}\)
B)\(\left(\frac{1}{125}-\frac{1}{1^3}\right)\cdot\left(\frac{1}{125}-\frac{1}{2^3}\right)\cdot...\cdot\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
C)\(\left(\frac{1}{38}-1\right)\cdot\left(\frac{1}{37}-1\right)\cdot\left(\frac{1}{36}-1\right)\cdot...\cdot\left(\frac{1}{2}-1\right)\)
HELP ME!!!!!!!!!!!!!!!!!!!
#)Giải :
a)\(2009^{\left(1000-1^3\right)\left(1000-2^3\right)...\left(1000-15^3\right)}=2009^{\left(1000-1^3\right)...\left(1000-10^3\right)...\left(1000-15^3\right)}=2009^0=1\)
b)\(\left(\frac{1}{125}-\frac{1}{1^3}\right)\left(\frac{1}{125}-\frac{1}{2^3}\right)...\left(\frac{1}{125}-\frac{1}{25^3}\right)=\left(\frac{1}{125}-\frac{1}{1^3}\right)...\left(\frac{1}{125}-\frac{1}{5^3}\right)...\left(\frac{1}{125}-\frac{1}{25^3}\right)=\left(\frac{1}{125}-\frac{1}{1^3}\right)...0...\left(\frac{1}{125}-\frac{1}{25^3}\right)=0\)
Giúp mik với
Tính nhanh:
a. A=\(\left(-1\right)^{2n}.\left(-1\right)^n.\left(-1\right)^{n+1}\left(n\in N\right)\)
b. B=\(\left(10000-1^2\right)\left(10000-2^2\right)\left(10000-3^2\right)..\left(10000-1000^2\right)\)
c. C=\(\left(\frac{1}{125}-\frac{1}{1^3}\right)\left(\frac{1}{125}-\frac{1}{2^3}\right)\left(\frac{1}{125}-\frac{1}{3^3}\right)...\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
d. D=\(1999^{\left(1000-1^3\right)\left(1000-2^3\right)\left(1000-3^3\right)...\left(1000-10^3\right)}\)
a) \(A=\left(-1\right)^{2n}.\left(-1\right)^n.\left(-1\right)^{n+1}=\left(-1\right)^{3n+1}\)
b) \(B=\left(10000-1^2\right)\left(10000-2^2\right).........\left(10000-1000^2\right)\)
\(=\left(10000-1^2\right)\left(10000-2^2\right)......\left(10000-100^2\right)....\left(10000-1000^2\right)\)
\(=\left(10000-1^2\right)\left(10000-2^2\right).....\left(10000-10000\right).....\left(10000-1000^2\right)=0\)
c) \(C=\left(\frac{1}{125}-\frac{1}{1^3}\right)\left(\frac{1}{125}-\frac{1}{2^3}\right)..........\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
\(=\left(\frac{1}{125}-\frac{1}{1^3}\right)\left(\frac{1}{125}-\frac{1}{2^3}\right).....\left(\frac{1}{125}-\frac{1}{5^3}\right)......\left(\frac{1}{125}-\frac{1}{25^3}\right)\)
\(=\left(\frac{1}{125}-\frac{1}{1^3}\right)\left(\frac{1}{125}-\frac{1}{2^3}\right)........\left(\frac{1}{125}-\frac{1}{125}\right).....\left(\frac{1}{125}-\frac{1}{25^3}\right)=0\)
d) \(D=1999^{\left(1000-1^3\right)\left(1000-2^3\right)........\left(1000-10^3\right)}\)
\(=1999^{\left(1000-1^3\right)\left(1000-2^3\right)........\left(1000-1000\right)}=1999^0=1\)