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 .
goi p l tap hop cac so tu nhien le ,lon hon 3 nhung ko lon hon 9.
a) mo ta tap hop p bang 2 cach ,
b) bieu dien cac phan tu cua tap hop p tren cung mot tia so.
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
tim x thuoc N
a,\(\dfrac{1}{4}\cdot\dfrac{2}{6}\cdot\dfrac{3}{8}\cdot...\cdot\dfrac{31}{64}=2^x\)
b,\(\left(x-3\right)^3=125^2\)
c,\(7^{x+2}+2\cdot7^{x-1}=345\)
d,\(3^{x-5}-81=0\)
bai hoi dai cac ban giup mk
Tim x \(\in\) N
a)\(^{3^{x-2}}\)
b)\(3.4^{x-2}\)=19.2
c)\(5^{x+1}+5^{x+2}\)=810
d)\(\left(x-1\right)^5-\left(x-1\right)^2=0\)
e)\(2^x-15=17\)
Cac ban oi cac ban lam giup minh voi mai minh phai nop bai roi
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,\(\left(3x+2\right)⋮\left(x+1\right)\)
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
A=35+36+...+320
a) tinh xem A co so hang tu
b)tinh A