630:[25.(1+5\(^0\))-2.4\(^2\)]
630:[25.(1+5\(^0\))-2.4\(^2\)]
=630:[25.(1+1)-2.16]
=630:[25.2-32]
=630:[ 50-32]
=630: 18
= 35
sửa đề nhanh thật, suýt nữa thì ấn gửi rồi
Tính giá trị biểu thức
a (-3)^10.15^5/25^3.(-9)^7
b 2^3+3(1/9)^0-2-2.4+((-2)^2/1:1/2).8
Tìm x, biết:
1) 1/3. x + 2/5. (x - 1) = 0
2) (2 x - 3).(6 - 2 x) =0
3) (3 x -1).(-1/2 x + 5) = 0
4) (2 x + 3/5)2 - 9/25 = 0
Tính:
1) 4/2.4 + 4/4.6 + 4/6.8 + ... + 4/2008.2010
2) 1/18 + 1/54 + 1/108 + ... +1/990
\(a,\frac{1}{3}x+\frac{2}{5}x-\frac{2}{5}=0\)
\(\frac{11}{15}x=\frac{2}{5}\)
\(x=\frac{6}{11}\)
b,\(\left(2x-3\right).\left(6-2x\right)=0\)
\(\Rightarrow\orbr{\begin{cases}2x-3=0\\6-2x=0\end{cases}\Rightarrow}\orbr{\begin{cases}x=\frac{3}{2}\\x=3\end{cases}}\)
Vậy
\(\left(3x-1\right).\left(-\frac{1}{2}x+5\right)=0\)
\(\Rightarrow\orbr{\begin{cases}3x-1=0\\-\frac{1}{2}x+5=0\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{1}{3}\\x=10\end{cases}}}\)\
Vậy
a)4/9. (-9)/4-509:-10/9
b)99/25-(22/5+1/2).25
c)2x-1/4=1/2
d)25%-9/2x-5/2.4^2=5,25
43,57*2,6*(630-315*2)
4/1*3+4/1*5+...+4/13*15
3/4+24%+0,76+25%
4/5*5/4*36%*2,5
tìm x e Z biết
7 ^ 2 . 5 - ( 2 . [ x ] + 3 ^ 0 ) = 630 : 3 ^ 2 .1 ^ 10
\(\Leftrightarrow49\cdot5-\left(2\left|x\right|+1\right)=70\)
=>2|x|+1=245-70=105
=>2|x|=104
=>x=52 hoặc x=-52
Câu 1:
(phần a lm r)
b) 120:{54-[50:2-(3\(^2\)-2.4)]}
Câu 2:
a) x-25=39 b) 3x - 6= 3\(^5\):3\(^2\)
a) x-25=39
b) 3x - 6 = 3
Tính nhanh
324:33-(25-2.42)+20100
\(\dfrac{25^2.4^2}{5^5.\left(-2\right)^5}=\dfrac{\left(25.4\right)^2}{\left(5.\left(-2\right)\right)^5}=\dfrac{\left(100\right)^2}{\left(-10\right)^5}=\dfrac{1}{-10}\)