Question

t^4-2t^2-3=0   2x^4-9x^2+4=0     (x^2-5x+4)(x^2-5x+6)=120

Answer 1

1)t^4-2t^2-3=0

t=z

t^2-2t-3=0

D=(-2)^2-4*1*(-3)=4+12=16

z1=2+4/2=3

z2=2-4/2=-1

(3.-1)

2) 2x^4-9x^2+4=0

x=t

D=(-9)^-4*2*4=81-32=49

t1=9+7/4=4

t2=9-7/4=1/2

(4.1/2)