xet tap e gom cac so tu nhien , moi so deu co nam chu so xep theo thu tu ko giam va tap cac chu so cua no la { 1,3,5,7}.
a) mo ta tap e bang cach liet ke cac phan tu cua no,
b) goi n la so lon nhat trong tap e . bieu dien n thanh tong gia tri cac chu so cua no .
tim so tu nhien n biet n thuoc N*\(\)
A=111...1211...1 la hop so (co n thua co 1)
mong cac thay co cung cac ban giup em bai nay
nho cac ban giup minh nhe
1.tim x thuoc N biet:
a)(2x+1)mu 3=125 b)(x-5)mu 4=(x-5)mu 6 c)2 mu x-15=17 d)(7x-11)mu 3=2 mu 5. 5mu 2+200
2.viet cac tich sau hoac thuong duoi dang luy thua cua mot so:
a)2 mu 5 . 8 mu 4 b)25.125 c)25 mu 5:25 mu 7
3.viet cac tich, thuong sau duoi dang luy thua:
a) 2 mu 10:8 mu 3 b)12 mu 7:6 mu 7 c)5 mu 8:25 mu 2
4.tinh gia tri cac bieu thuc sau:
a mu3 . a mu 9 (a mu 5)mu7 (a mu 6)mu 4. a mu 12 4.5 mu 2-2.3 mu 2
sa p xep luy thua tu lon den be
\(2^{100}< 3^{75}< 5^{50}\)
ca c ba n so sa nh ra roi ha y la m cho mk nhe
mot so hai chu so , trong do hieu cua chu so hang don vi va chu so hang chuc bang 8.hoi do la so nao ?
tinh nhanh
a,48x19+48x115+124x52
b.27x121-87x27+73x34
c.125x98-125x46-52x25
d,136x23+136x17-40x36
e,17x93+116x83+17x23
g,19x27+47x81+19x20
h,87x23+13x93+70x87
cac ban oi nhung so nao tach ra de tinh nhanh duoc thi cac ban hay tach ra nha cam on nhieu ai nhanh mik cho 1 like
A=35+36+...+320
a) tinh xem A co so hang tu
b)tinh A
tim x thuoc N
a,\(21x-1⋮11\)
b,\(5x+1⋮7\) va x la STN lon nhat co 3 chu so
c,\(3x-2⋮11\) va \(100< x< 2017\)
d,\(5⋮\left(x-3\right)\)
e,\(\left(3x+2\right)⋮\left(x+1\right)\)
tinh gia tri cua bieu thuc 1+2 ( 25 + 9 ) - 4^3 =