5a 4x² + 4x +1 = ( 2x+1 )²
b ( 4x² +4x +1 ) + ( y² -2y +1 )= 0
( 2x+1 )² + ( y-1 )² =0 daca 2x+1 =0 ; 2x =-1 ; x = -1/2
y-1 =0 ; y= 1
4 . f(x ) =2x+1
A ( 2 , f(2) ) f(2 ) = f(2) = 5 A (2,5) atunci M( 2,0 )
B( -1 , f(-1)) f(-1) = -1 B( -1 ,-1) atunci N ( 0,-1)
