Question

Folosind proprietatile proportiilor,rezolvati ecuatiile:
a) x/3=3/x,x∈R⇒x²=
b)5/2x=1/x,x∈N⇒x²=
c)2/x=-x/2,x∈Q⇒x²=

Answer 1

a. x²=9, x²-9=3, (x-3)(x+3)=0, x1=3, x2=-3
b. x²=2/5, x=+-√2/√5=+-√10/5, x∉N nu are sol
c. 2/x=-x/2,-x²=4,x²+4=0 nu are sol in Q