Question

Stiind ca a+b=4 si a*b=2, calculati 1/a+1/b ( 1 supra a + 1 supra b )
Stiind ca a+b=4 si ac+ad+bc+bd=4√3, calculati c+d

Answer 1

1/a+1/b= aducem la acelasi numitor comun
(a+b)/a*b=4/2=2

ac+ad+bc+bd=4√3
a(c+d)+b(c+d)=4√3
(c+d)(a+b)=4√3
(c+d)*4=4√3
c+d=4√3:4
c+d=√3