# Vectors

if |x|=2 and |y|=5, determine the dot product between x-2y and x+3y if the angle between vector x and y is 60deg.

1. 👍
2. 👎
3. 👁
1. say X = 2 i + 0 j
Y = 5 cos 60 i + 5 sin 60 j
Y = 2.5 i + 4.33 j

then
X - 2Y = -3 i - 8.66 j
X + 3Y = etc, I think you can do it from there

1. 👍
2. 👎

## Similar Questions

1. ### Calculus

A searchlight rotates at a rate of 2 revolutions per minute. The beam hits a wall located 8 miles away and produces a dot of light that moves horizontally along the wall. How fast (in miles per hour) is this dot moving when the

2. ### calculus

A searchlight rotates at a rate of 4 revolutions per minute.? The beam hits a wall located 13 miles away and produces a dot of light that moves horizontally along the wall. How fast (in miles per hour) is this dot moving when the

3. ### Math

For questions 1-10, match each inequality with its corresponding solution by entering the capital letter only. For example, type "A" only. A. x-1>5 B.2x≤6 C.x-7>-4 D.-2x -3, open dot at -3 and shaded to the right 4.x 3, open dot

4. ### Vectors: Dot product

Given a and b unit vectors if |a+b|=square root 3, determine (2a-5b)dot(b+3a) First I foiled the whole thing: =2(a dot b)+ 6 (a dot a) - 5(b dpt b) -15(a dot b) =-13(a dot b) + 6(a dot a) - 5(b dot b) =-13(1)(1)+6-5 =-13+1 =-12

1. ### Calculus

Find the value of 2 over 9 minus 4 over 27 plus dot dot dot plus the quotient of the product of negative 1 raised to the n plus 1 power and 2 to the nth power and the quantity 3 raised to the n plus 1 power plus dot dot dot . (10

2. ### Calculus

PLEASE HELP ME! What is the x-coordinate where the graph of the function represented by the Maclaurin series 1 minus 2 times x plus 4 times x squared over 2 factorial minus 8 times x cubed over 3 factorial plus dot, dot, dot,

3. ### Vectors

If vector a and b are unit vectors, and |a+b|= root3, determine (2a-5b) dot product(b+3a)

4. ### TRIGONOMETRY

Use the dot product to determine which of the following vector pairs are orthogonal. a. v1 = (-5,5) and v2 = (1,1) b. v1 = (154,169.4) and v2 = (88,64)

How can you determine if the given lines are perpendicular? Line 1: (-1,3) and (3,-3) Line 2: (-3,0) and (3,3) A)determine if they have slopes with opposite values*** B)determine if they have the same slope C)determine if the

2. ### math calculus

if i,j,k are the standard unit basic vectors, in 3 space, determine the value of k dot(j-3k)+(i-4k) dot (i-4k)-8 |i cross -k| (Simplify without using components)

3. ### calculus

Gandalf the Grey started in the Forest of Mirkwood at a point with coordinates (−2,3) and arrived in the Iron Hills at the point with coordinates (−1,7). If he began walking in the direction of the vector v=3i+2j and changes

4. ### physics

When the thigh is fractured, the patient's leg must be kept under traction. One method of doing so is a variation on the Russell traction apparatus. (See the figure.) Please place period in place of (dot)