Respuesta :

Answer:

The sum of the two vectors is the vector <-0.5 , 4+3.5[tex]\sqrt{3}[/tex] >

Step-by-step explanation:

The horizontal component (x) of a vector whose magnitude is b units and its direction is Ф° is b cos Ф

The vertical component (y) of a vector whose magnitude is b and its direction is Ф is b sin Ф

The vector is <b cos Ф , b sin Ф>

∵ The vector goes 7 units at an angle [tex]\frac{2\pi }{3}[/tex]

- That means its magnitude is 7 and its direction is  [tex]\frac{2\pi }{3}[/tex]

∴ x = 7 cos(  [tex]\frac{2\pi }{3}[/tex] )

∴ y = 7 sin(  [tex]\frac{2\pi }{3}[/tex] )

∵ cos(  [tex]\frac{2\pi }{3}[/tex] ) =  [tex]-\frac{1}{2}[/tex]

∵ sin(  [tex]\frac{2\pi }{3}[/tex] ) =  [tex]\frac{\sqrt{3}}{2}[/tex]

- Substitute them in x and y

∴ x = (7)( [tex]-\frac{1}{2}[/tex] )

∴ x = -3.5

∴ y = (7)( [tex]\frac{\sqrt{3}}{2}[/tex] )

∴ y = 3.5[tex]\sqrt{3}[/tex]

The vector is <-3.5 , 3.5[tex]\sqrt{3}[/tex]>

Now lets add the vectors by adding xs and ys components

∵ <3 , 4> + <-3.5 , 3.5[tex]\sqrt{3}[/tex] > = <3 + -3.5 , 4 + 3.5[tex]\sqrt{3}[/tex] >

∴  <3 , 4> + <-3.5 , 3.5[tex]\sqrt{3}[/tex]> = <-0.5 , 4+3.5[tex]\sqrt{3}[/tex] >

The sum of the two vectors is the vector <-0.5 , 4+3.5[tex]\sqrt{3}[/tex] >