Chung minh rang a/b = c/d thi a/b = a +(-) c/ b +(-) d
choA= a+b-5 B=-b-c+1 C=b-c-4 D=b-a. Chung minh rang A+b= C-D
Chung minh rang voi moi a,b,c,d, la cac so nguyen thi T=(a-b)(a-c)(a-d)(b-c)(c-d) chia het cho 12
cho 2 p/s a/b vs c/d (a,b,c,d la cac so nguyen duong ) chung minh rang neu a/b < c/d thi b/a > d/c
cho a,b,c thuoc z , chung minh rang : a(c-b) - b(-a-c) =c(a+b0
cho a/b=c/b chung minh rang a^2+c^2/b^2+c^2
tra biet ai ra de nay ma doc tra hieu gi ca :
cho a = b , b=c , c=>d , d=e .123456789
chung minh rang e=a
cho a+b=c+d
va a^2+b^2=c^2+d^2
chung minh rang
a^2018+b^2018=c^2018+d^2018