Cual es el modulo del vector diferencia (a - b) entre dos vectores que forman un angulo de 30° entre si y cuyos módulos son 2m y 8m. Grafica (Les agradecería muchísimo si me ayudan)

|a-b|=6.34m

Explanation:

To find the difference between the vector you can use the formulas for the magnitude of a vector and also for the doc product between two vectors:

a1, a2, a3: components of a vector

b1, b2, b3: components of b vector

a: magnitude of a = 2m

b: magnitude of b = 8m

angle = 30°

By squaring the first two equations

Then, you multiply by 2 the third equation:

Now, you sum the first two equations ans take the difference with the third equation. Thus, you obtain a perfect square trinomial:

This last expression is the square of the magnitude of the difference a-b. Hence you have:

thus, the magnitude of the difference is 6.34m

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

read more on -

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.