Question

|(x-4)(x-5)| =0 Ofer coroniță

Answer 1

|x*x-x*5-4*x+4*5|=0
|x la puterea 1+1-x*5-4*x+4*5|=0
|x la a2a-x*5-4*x+4*5|=0
|x patrat-5x-4*x+4*5|=0
|x patrat-5x-4x+4*5|=0
|x patrat-9x+4*5|=0
|x patrat-9x+20|=0
x patrat-9x+20=0
x pateat-9x=-20
x=9+radical din (-9) la a 2a-4*20/2*1
x=9+radical din (-9) la a2a-4*20/2
x=9+radical din 9la a2a-4*20/2
x=9+radical din 1/2
x=9+1/2
x=9-1/2
x=10/2
x=9-2/2
x=5
x=9-1/2
x=5
x=8/2
x=5
x=4
x apartine lui {4,5}