Answer:
Step-by-step explanation:
The formula for the dot product of vectors is
u·v = |u||v|cosθ
where |u| and |v| are the magnitudes (lengths) of the vectors. The formula for that is the same as Pythagorean's Theorem.
which is 
which is 
I am assuming by looking at the above that you can determine where the numbers under the square root signs came from. It's pretty apparent.
We also need the angle, which of course has its own formula.
where uv has ITS own formula:
uv = (14 * 3) + (9 * 6) which is taking the numbers in the i positions in the first set of parenthesis and adding their product to the product of the numbers in the j positions.
uv = 96.
To get the denominator, multiply the lengths of the vectors together. Then take the inverse cosine of the whole mess:
which returns an angle measure of 30.7. Plugging that all into the dot product formula:
gives you a dot product of 96
Jenny average swimming speed was 2.5 km/h, her average biking speed was 24 km/h and her average running speed was 12 km/h.
<h3>Speed</h3>
Speed is the ratio of total distance travelled to total time taken. It is given by:
Speed = distance / time
Let a represent the average swimming speed, b the average biking speed and c the average running speed.
Her average biking speed was 2 times her average running speed, hence:
Her average running speed was 8 times her average swimming speed. Hence:
Total distance of the triathlon was 55.5 kilometers. Hence:
a * 1 hour + b * 1.75 hour + c * 1 hour = 55.5 (3)
From equation 1, 2 and 3:
a = 2.5, b = 24, c = 12
Jenny average swimming speed was 2.5 km/h, her average biking speed was 24 km/h and her average running speed was 12 km/h.
Find out more on speed at: brainly.com/question/6504879
Answer:
2
Step-by-step explanation:
Simplify the expression.
Answer:
1/2 a bag
Step-by-step explanation:
1/2 a piece is smaller than 1/2 a bag because the bag is bigger
