Cho bieu thuc
\(a=1+7+7^2+7^3+...+7^{100}\)
a) Tinh a
b) Tim x biet \(6a+1=7^x\)
c) Tim du trong phep chia a cho 8
tim x biet:
a)|x|=5
b)|x|+3=7
c)\x|-2=3
d)|2x-4|+7=10
tim x biet : a,-12/21×x + 3/7=-4/3, b, 2x +-3^2=5/4 , c, 75% x- 2/5=3/10, d, (3x-2)×(x+7)
tim so nguyen x, biet
a. 7 - x = 8 - ( -7 )
b. x - 8 = ( -3 ) = -8
tim so nguyen a, biet
a. gia tri tuyet doi a gia tri tuyet doi = 2
b. gia tri tuyet doi a + 2 gia tri tuyet doi = 0
ai biet giup minh voi
| - 18 | + ( - 12) va 2^3 .2^2+ 5^7 : 5^5 - 3^2 .6
va tim x biet
3^10 : ( 43- 4x ) = 3^7
tim x biet 2.(x-5)-3.(x+7)=14
tim x la stn biet
a, 2.52=53
b,[3(x+2):7].4=120
c,(x-5)4=(x-5)2
d,123-5.(x+4)=38
Tim x biet.
a/x+5+x-7+x-9=x-5+x-2
b/9(2x-3)+5=4(4-1)-8
c/2=-(×-1)^5+34
d/7=-|x-5|+10
Tim x biet
a)x - \(\frac{5}{7}=\frac{1}{9}\)
b) \(\frac{-3}{7}-x=\frac{4}{5}+\frac{-2}{3}\)
