Respuestas
Al resolver cada ecuación se obtiene:
a. x²+2x-15 = (x-3)(x+5)
b. x²-13x-30 = (x-10)(x-6)
c. 5x²-12x+4 = (x-5)(x-2/5)
d. 4x²+12x-16 = (x-1)(x+4)
e.. x²+10x-7 = (x+5-4√2)(x+5+4√2)
f. 9x²+10x+1 = (x+1/9)(x+1)
Explicación paso a paso:
La resolvente: x = (-b±√b²-4ac)/2a
a. x²+2x-15 =0
Aplicar la resolvente;
x = (-2±√2²-4(-15))/2
x = (-2±√64)/2
x = (-2±8)/2
x = 3
x =-5
x²+2x-15 = (x-3)(x+5)
b. x²-13x-30 =0
Aplicar la resolvente;
x = (13±√13²-4(-30))/2
x = (13±√49)/2
x = (13±7)/2
x = 10
x =6
x²-13x-30 = (x-10)(x-6)
c. 5x²-12x+4 =0
Aplicar la resolvente;
x = (12±√12²-4(5)(4))/10
x = (12±√64)/10
x = (12±8)/10
x = 2
x =2/5
5x²-12x+4 = (x-5)(x-2/5)
d. 4x²+12x-16 =0
Aplicar la resolvente;
x = (-12±√12²-4(-16)(4))/8
x = (-12±√400)/8
x = (-12±20)/8
x = 1
x =-4
4x²+12x-16 = (x-1)(x+4)
e. x²+10x-7 =0
Aplicar la resolvente;
x = (-10±√10²-4(-7))/2
x = (-10±√128)/2
x = (-10±8√2)/2
x = -5+4√2
x = -5-4√2
x²+10x-7 = (x+5-4√2)(x+5+4√2)
f. 9x²+10x+1 =0
Aplicar la resolvente;
x = (-10±√10²-4(9))/18
x = (-10±√64)/18
x = (-10±8)/18
x = -1/9
x =-1
9x²+10x+1 = (x+1/9)(x+1)
a = 9; b = -12; c = +4;
Δ = b2-4ac
Δ = -122-4·9·4
Δ = 0
Delta es igual a cero, por lo que solo hay una solución para la ecuación
x=−b/2a =12/18 =2/3