Question

exercitiul 3 va rog .

Answer 1

[tex] \frac{2x+3}{x+2} = \frac{x-1}{x-2} [/tex]
(2x+3)(x-2)=(x+2)(x-1)
2x²-4x+3x-6=x²-x+2x-2
2x²-x²-4x+3x+x-2x=-2+6
x²-2x=4
x²-2x-4=0
a=1     b=-2     c=-4
Δ=b²-4ac
Δ=(-2)²+16
Δ=4+16
Δ=20
x₁=$\frac{-b- \sqrt{delta} }{2a}= \frac{2- \sqrt{20} }{2}= \frac{2- 2\sqrt{5} }{2} = 2- \sqrt{5}$
x₂=$\frac{-b+ \sqrt{delta} }{2a}= \frac{2+ \sqrt{20} }{2} = \frac{2+2 \sqrt{5} }{2} =2+ \sqrt{5}$
S={2-√5, 2+√5}