Cho n thuoc N, chung to cac phan so sau la toi gian :
a, 2n+1/5n+2
b, 5n+2/3n+1
c, 5n+2/(3n+1).(2n+1)
tim cac so tu nhien n de cac phan so sau la phan so toi gian a) 2n+3:4n+1 b) 3n+2:7n+1 c) 2n+7:5n+2
Tim cac so tu nhien n de cac phan so sau la phan so toi gian:
a)2n+3/4n+1 b) 3n+2/7n+1 c)2n+7/5n+2
Mình xin lỗi , mình xin chịu lúc nào mình nghĩ ra thì mình sẽ giúp cậu
Tìm n đẻ cac phan so sau toi gian
3n+2/7n+1
2n+7/5n+2
8n+193/4n+3
6n+99/3n+4
chung minh 5n+3/3n+2la phan so toi gian (n thuoc Z)
tim n thuoc N de cac ap so sau nguyen to cung nhau
a) 3n + 2va 7n+1
b) 2n+7 va 5n+2
Cho phan so: P = \(\frac{2n+7}{5n+2}\)(n thuoc Z)
a)Tim n thuoc z de P la phan so chua toi gian.
b)Tim n thuoc Z sao cho P la phan so toi gian.
CMR phan so 3n+2/5n+3 toi gian voi moi n thuoc N
Chung to rang :
a)(2n + 1) (2n+2) chia het cho 3 . Voi n thuoc so tu nhien
b)(5n+1) (5n+2) chia het cho 6. Voi n thuoc so tu nhien.
tim các gioi han sau
a) \(\dfrac{n^2-2n}{5n+3n^2}\)
b) \(\dfrac{n^2-2}{5n+3n^2}\)
c) \(\dfrac{1-2n}{5n+3n^2}\)
d) \(\dfrac{1-2n^2}{5n+5}\)
a,\(lim\dfrac{n^2-2n}{5n+3n^2}=lim\dfrac{1-\dfrac{2}{n}}{\dfrac{5}{n}+3}=\dfrac{1}{3}\)
b,\(lim\dfrac{n^2-2}{5n+3n^2}=lim\dfrac{1-\dfrac{2}{n^2}}{\dfrac{5}{n}+3}=\dfrac{1}{3}\)
c,\(lim\dfrac{1-2n}{5n+3n^2}=lim\dfrac{1-2n}{n\left(5+3n\right)}=lim\dfrac{\dfrac{1}{n}-2}{1\left(\dfrac{5}{n}+3\right)}=-\dfrac{2}{3}\)
d,\(lim\dfrac{1-2n^2}{5n+5}=lim\dfrac{\left(1-n\sqrt{2}\right)\left(1+n\sqrt{2}\right)}{5n+5}=lim\dfrac{\left(\dfrac{1}{n}-\sqrt{2}\right)\left(\dfrac{1}{n}+\sqrt{2}\right)}{5+\dfrac{5}{n}}=\dfrac{-2}{5}\)