Question

Ecuati de gradul 2 .
1. X²+x-6=0
2. -X²+2X-1=0
3. 2X²-50=0
4. -x²+9=0
5. -x²+3x-2=0

Answer 1

Explicație pas cu pas:

x²+x-6=0 => x²+3x-2x-6=0 => x(x+3)-2(x+3)=0 =>(x+3)(x-2)=0 <=>

x+3=0 => x=-3 sau x-2=0=> x=2

-x²+2x-1=0 <=> x²-2x+1=0 =>(x-1)²=0 =>

x-1=0 =>x=1

2x²-50=0 => 2x²=50 => x²=25 =>x1=5 sau x2=-5

-x²+9=0 => x²=9 => x1=3 sau x2=-3

-x²+3x-2=0 => x²-3x+2=0 =>x²-x-2x+2=0 =>

x(x-1)-2(x-1)=0 => (x-1)(x-2)=0 =>

x-1=0 =>x=1 sau x-2=0=> x=2