Theorem of cosine:
a²=b²+c²-2bc(cos α) ⇒cos α=-(a²-b²-c²) / 2bc
In this case:
a=15 cm
b=10 cm
c=5 cm
cos α=-(15²-10²-5²) / 2*10*5
cos α=-100 / 100
cos α=-1
A=arc cos -1=180º This is impossible, because:
A+B+C=180º; then B=C=0º This is impossible for make a triangle (B>0 and C>0 if we want to make a triangle).
Therefore: it is not possible can make a triangle with side lengths of 5 cm, 10 cm and 15 cm.
Step-by-step explanation:
Question?
Respuesta:
(2945.411; 3054.589)
Explicación paso a paso:
Dado ;
Tamaño de la muestra, n = 50
Media, xbar = 3000
Desviación estándar, s = 200
Nivel de confianza, Zcrítico al 95% = 1,96
El intervalo de confianza se define como:
Xbar ± margen de error
Margen de error = Zcrítico * s / sqrt (n)
Margen de error = 1,96 * 200 / sqrt (50)
Margen de error = 54.589
Límite inferior = (3000 - 54.589) = 2945.411
Límite superior = (3000 + 54.589) = 3054.589
(2945.411; 3054.589)