Question

descubra pela descriminante quantas raízes tem cada equação:
a) 3x²-5x+3=0
b) -x²+10x-25=0
c)5x²-x-1=0

Answer 1

a)3x^2+5x+3=0》a=3,b=5,c=3》X=-b-,+\/b^2-4ac/2a》X=-5-,+\/5^2-4(3)(3)/2(3) X=-5-,+\/25-36/6 X=-5-,+\/-11/6》 X= -5-,+nao existe raiz/6》X=E. b)-x^2+10x-25=0 》a=1,b=10,c=-25》 X=-b-,+\/b^2-4ac/2a. X=-10-,+\/10^2-4(-1)(-25)/2(-1) X=-10-,+\/100+4(-25)/- 2. X=-10-,+\/100-100/- 2. X=-10-,+\/0/- 2》X=-10-,+0/ - 2. X1=-10+0/-2》X1=-10/-2》X1=5 X2=-10-0/2》X2=-10/-2》X2=5 c)5x^2-x-1=0》a=5,b=-1,c=-1》X=-b-,+\/b^2-4ac/2a》 X=-(-1)-,+\/(-1)^2-4(5)(-1)/2(5) X=1-,+\/1-20(-1)/10. X=1-,+\/1+20/10》X=1-,+\/21/10. X=1-,+4,58/10. X1=1+4,58/10》X1=5,58/10z(÷2)》X1=2,79/5》X1=0,558》X1=0,56. X2=1-4,58/10》X2=-3,58/10(÷2) X2=-1,79/5》X2=-0,358》X2=-0,36