Question

sa se calculeze a patrat+b patrat ,stiind ca numerele a si b au suma egala cu 4 si podusul cu 3

Answer 1

$( a+b )^{2}$ = $a^{2} + b^{2} + 2ab$ =>
=> $4^{2}$ = $a^{2} + b^{2}$ + 2·3 => 16 = $a^{2} + b^{2}$ + 6 =>
=> $a^{2} + b^{2}$ = 10

Answer 2

a+b=4
a*b=3
a=4-b
(4-b)*b=3
4b-b*b=3(inmultesti cu -1)
b*b-4b+3=0
delta=16-12=4=2*2
b1=(4-2)/2=1
b2=(4+2)/2=3
a1=4-1=3
a2=4-3=1
a patrat + b patrat = 9+1 sau 1+9 =10