Question

(2x-3)(2x+3)=(x+5)do kwadratu-9

2x(x-3)-(x+1)(x+2)=(2x-3)do kwadratu

(2x-1)do kwadratu-(4x+1)(4x-1)=4x(1-2x)

plis potrzebne na jutro!!!

Answer 1

a) (2x-3)(2x+3)=(x+5)²-9 

 4x²-9=x²+10x+25-9

3x²-10x-25=0

Δ=400

√Δ=20

x₁=10-20/6 = -5/3

x₂=10+20/6 = 5

 

b)2x(x-3)-(x+1)(x+2)=(2x-3)²

2x²-6x-x²-2x-x-2=4x²-12x+9

-3x²+3x-11=0

Δ<0

 

c)(2x-1)²-(4x+1)(4x-1)=4x(1-2x)

4x²-4x+1-16x²+1=4x-8x²

-4x²-8x+2=0

2(-2x²-4x+1)=0

Δ=8

√Δ=2√2

x₁=4-4√2/4= 4(1-√2)/4 = 1-√2

x₂=4+4√2/4= 4(1+√2)/4 = 1+√2