tim a thuoc Z sao cho :
a (a+2)<0
bai 2
a)chung to rang P=4a2+4a chia het cho 8 voi moi a thuoc z
b)tim a thuoc z sao cho Q=a+7 chia het cho a (a khac 0)
c)tim a thuoc z sao cho M=a+1 chia het a -2 (a khac 2)
cho A=27a-37/4-5a.
a,tim a de A=2. b,Tim a thuoc Z de A thuoc Z. c,Tim a thuoc Z de A co gia tri lon nhatcho A=27a-37/4-5a.
a,tim a de A=2.
b,Tim a thuoc Z de A thuoc Z.
c,Tim a thuoc Z de A co gia tri lon nhat
Very easy, mình giúp 1 câu, các câu còn lại bạn tự làm đi
a,\(\frac{27a-37}{4-5a}=2\Rightarrow27a-37=8-10a\Rightarrow37a=45\Rightarrow a=\frac{45}{37}\)
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.
tim a,b thuoc z sao cho 2ab=a+b
\(2ab=a+b\)
\(a-2ab+b=0\)
\(2a-2.2ab+2b=0\)
\(2a-2b\left(2a-1\right)=0\)
\(2a-1-2b\left(2a-1\right)=-1\)
\(\left(2a-1\right)\left(1-2b\right)=-1\)
\(\Rightarrow2a-1=1\) thì \(1-2b=-1\) \(\Rightarrow a=1\) thì \(b=1\)
\(\Rightarrow2a-1=-1\) thì \(1-2b=1\) \(\Rightarrow a=0\) thì \(b=0\)
Vậy \(\left(a;b\right)=\left(0;0\right)\left(1;1\right)\)
3) Tim n thuoc Z sao cho :
a)3n+1chia het cho (n-2)
b)4n-3 chia het cho (2n+3)
4)tim x,y thuoc Z sao cho :
a)xy-3x-y-6=7
b)2xy+10y + x =5
ai nhanh minh tick cho
tim a thuoc z
sao cho a.(a - 3)>0
cho a;b thuoc Z tim x sao ch x+a=10
cho A=n+3\n-2 (n thuoc Z)
a) tim n de A la phan so
b) tim n de A thuoc Z
c) tim n biet A=-4