Question

Heeellpppp?!! dau coroana

Answer 1

9. A) (3x+2y+1)^2=(3x)^2+(2y)^2+1=9x^2+4y^2+1 B)x^2-2xy+y^2=(x-y)^2. 10.a) x^2=0 =>x0; b)x^2-1=> x^2=0+1=1; c)x^2+1=0=>x^2=0-1=-1; d) x^2-3-2√2=0=>x^2=0+3+√8=3+√8.