Question

(x^2-3x)^2 -3 (x^2-3x) = 4

Answer 1

x²-3x=t
t²-3t=4
t²-3t-4=0
Δ=9+16=25, √Δ=5
t1=(3+5)/2=4. x²-3x=4, x²-3x-4=0, Δ=9+16=25, √Δ=5, x1=(3+5)/2=4,
x2=(3-5)/2=-1
t2=(3-5)/2=-1, x²-3x=-1, x²-3x+1=0, Δ=9-4=5, √Δ=5
x3=(3+√5)/2, x4=(3-√5)/2